SB2215E01 Oct.
Important Safety Information Most accidents involving product operation, maintenance and repair are caused by failure to observe basic safety rules or precautions. An accident can often be avoided by recognizing potentially hazardous situations before an accident occurs. A person must be alert to potential hazards. This person should also have the necessary training, skills and tools to perform these functions properly.
Index GENERAL INFORMATION .......................................4 How to Read This Manual ....................................4 Precaution Before Service ....................................6 General .................................................................8 Tightening Torque .................................................9 Sealant ................................................................12 Alternator ............................................................47 IGNITION SYSTEM .........
DUAL FUEL SYSTEM ...........................................102 General ..................................................187 Engine ....................................................189 Carburetor ..............................................190 Electrical Components ...........................192 GOVERNING SYSTEM .........................................103 General Description ..........................................103 Governor,Disassembly and Reassembly ..........104 SPECIAL TOOLS ..............
GENERAL INFORMATION How To Read This Manual Scope of Explanation This book describes the service procedures for the engine removed from the vehicle. For procedures concerning removal of the engine from the vehicle and on-vehicle inspection and servicing, refer to the appropriate service manuals separately prepared for the individual models.
FRONT CASE AND OIL PAN REMOVAL AND INSTALLATION 6EN1898 Removal steps N M A L K B J C I H 1. Oil filter 2. Oil pressure switch 3. Drain plug 4. Drain plug gasket 5. Oil pan 6. Oil screen 7. Oil screen gasket 8. Plug 9. O-ring 10. Flang bolt 11. Relief plug 12. Gasket 13. Relief spring 14. Relief plunger 15. Oil filter bracket 16. Oil filter bracket gasket MD998727 G G G F E D D E E C B A 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30.
Precautions Before Servce Removal and Disassembly For prevention of wrong installation or reassembly and for ease of operation, put mating marks to the parts where no function is adversely affected. 1EN0018 Special Tool Be sure to use Special Tools when their use is specified for the operation. Use of substitute tools will result in malfunction of the part or damage it. 1EN0019 Tightening Torque Tighten the part properly to specified torque. 1EN0020 SE AL AN T Sealant Use specified brand of sealant.
Replacement Part When oil seal, O-ring, packing and gasket have been removed, be sure to replace them with new parts. However, rocker cover gasket may be reused if it is not damaged. 1EN0022 Rubber Parts Do not stain timing belt and V-belt with oil or water. Therefore, do not clean the pulley and sprocket with detergent. 1EN0023 Oil and Grease Before reassembly, apply specified oil to the rotating and sliding parts. 1EN0024 Genuine Part When the part is to be replaced, be sure to use genuine part.
General Engine models and numbers Engine model Fuel type G424 Gasoline, LPG, LPG (Low Emission Version) Indication of engine model and number The engine model and serial number are stamped on the right side of cylinder block surface.
Tightening Torque Major Bolts and Nuts Torque Item Remarks kg•m lb•ft N•m Water pump pulley bolt 0.9 6.5 9 Crankshaft pulley bolt 2.5 18.1 25 Spark plug 2.5 18.1 25 Distributor nut 1.2 8.7 12 Timing belt cover bolt 1.1 8.0 11 0.9 6.5 9 Tensioner spring spacer 4.9 35.4 48 Tensioner bolt 4.9 35.4 48 Oil pump sprocket nut 5.5 39.8 54 Crankshaft bolt 12.0 86.8 118 Tensioner B bolt 1.9 13.7 19 Counterbalance shaft 4.6 33.3 45 Engine support bracket bolt 3.
Torque Item Remarks kg•m lb•ft N•m Drain plug 4.0 28.9 39 Oil pan bolt 0.7 5.1 7 Oil screen bolt/nut 1.9 13.7 19 Oil pressure switch 1.0 7.2 10 Front case, Plug 2.4 17.4 24 doil pan Flange bolt 3.7 26.8 36 Relief plug 45 32.5 44 Oil filter bracket 1.9 13.7 19 Oil pump cover bolt 1.7 12.3 17 Oil pump cover screw 1.0 7.2 10 Front case bolt 2.4 17.4 24 Piston, Connecting rod bearing nut connecting rod. Flywheel bolt Crankshaft, cylinder block 13.5 97.
General Bolts and Nuts Tightening Torque Standard Bolts and Nuts Torque, kg•m (lb•ft) [N•m] Nominal diameter Pitch Bolt, stud, nut (with spring washer) Flange bolt, flange nut Head mark 4 Head mark 7 Head mark 10 Head mark 4 Head mark 7 M5 M5 - 0.5 (0.5) [3.6] - - 0.6 (4.3) [5.9] M6 M6 - 0.9 (6.5) [8.8] 1.2 (8.7) [12] - 1.0 (7.2) [9.8] M7 M7 1.2 (8.7) [12] 2.2 (15.9) [22] 3.0 (21.7) [29] 1.3 (9.4) [13] 2.4 (17.4) [24] M8 M8 2.5 (18.1) [25] 4.5 (32.5) [44] 6.0 (43.
Sealant Part to be Applied Brand TM Semi circular packing 3M AAD Part No.8672 or equivalent Rocker cover 3MTM AAD Part No.8672 or equivalent Oil pressure switch 3MTM AAD Part No.8672 or equivalent Oil pan Silicone RTV sealant or eguivalent Rear oil seal case Silicone RTV sealant or eguivalent Rear plate bolt 3MTM AAD Part No.8672 or equivalent Oil seal case bolt 3MTM AAD Part No.
SPECIFICATIONS General Specifications Engine model Item G424 Type Water-cooled, 4-cycle, gasoline-powered and L.P.G.-powered No. of cylinders and arrangement 4, in-line Combustion chamber type Semi-spherical Valve mechanism OHC 3 Total displacement, cm (cc) [cu in.] 2350 (2350) [143] Bore x stroke, mm (in.) 86.5 B 100 (3.41 B 3.94) Dry weight, kg (lb) 146 (322) Compression ratio 8.6 2 Compression pressure, kPa (kgf/cm ) [psi] Valve timing 1128 (11.5) [163.
Service Specifications Unit : mm(in.) Standard value Item Flatness of gasket surface Total resurfacing depth of both 0.2 (0.008) cylinder head and cylinder block Cylinder head Camshaft Overall height 89.9 to 90.1 (3.539 to 3.547) Oversize rework dimensions of valve guide hole 0.05 (0.0020) 13.05 to 13.07 (0.5138 to 0.5146) 0.25 (0.0098) 13.25 to 13.27 (0.5217 to 0.5224) 0.50 (0.0197) 13.50 to 13.57 (0.5315 to 0.5343) Intake Oversize rework dimensions of Exhaust valve seat ring hole 0.30 (0.
Unit : mm(in.) Item Standard value Limit No. 1 ring 0.25 to 0.40 (0.0098 to 0.0157) 0.8 (0.031) No. 2 ring 0.45 to 0.60 (0.0177 to 0.0236) 0.8 (0.031) Oil ring 0.20 to 0.60 (0.0079 to 0.0236) 1.0 (0.039) Ring-to-ring groove No. 1 0.03 to 0.07 (0.0012 to 0.0028) clearance No.
Unit : mm(in.) Item Standard value Starter motor Nominal output, kW No-load characterstics 11.0 Current, A 90 or less 3000 Outer diameter Runout 29.4 (1.16) 28.8 (1.13) 0.05 (0.0020) 0.1 (0.0039) 0.5 (0.020) 0.2 (0.008) Undercut Pinion gap 0.5 to 2.0 (0.020 to 0.
1. Stop engine if in use. MAINTENANCE G424 engine requires a certain amount 2. Allow sufficient time (approximately 2 minutes) for the oil to drain back into the oil pan. of maintenance. Suggested maintenance requirements 3. Remove dipstick. Wipe clean and reinstall. Push dipstick all the way into the dipstick tube. are contained in this section. The owner should, however, develop his own maintenance schedule 4. Remove dipstick and note the oil level.
• Lube oil filter gasket with engine oil. • On open systems carefully remove cooling system pressure cap. Coolant level will be approximately 3040 mm below pressure cap sealing surface. If level is low replace pressure cap and repair any/all other leaks. • Install oil filter as per filter manufacturers instructions. DO NOT OVER TIGHTEN • Fill crankcase with engine oil. • Start engine & run approximately 60 seconds. • Shut down engine, wait approximately 2 - 5 minutes and then check oil level.
Replace LP Fuel Filter Element Park the lift truck in an authorized refueling area with the forks lowered, parking beake applled and the transmission in NEUTRAL. 5 4 3 1 2 6 4. Remove cover (5), magnet (4), spring (3) and filter element (2) from bottom cover (1). 5. Replace the filter element (2). 6. Check bottom cover O-ring seal (6) for damage. Replace it if necessary. 7. Install the filter element (2), spring (3), magnet (4) and cover (5) on bottom cover (1). Align the scribe line on the covers.
Replace Gasoline Fuel Filter (Gasoline Truck and Dual Fuel Truck) Inspect Complete Exhaust System for Leaks, Damage • Perform visual inspection of exhaust system. • Repair any/all leaks found. WARNING Fuel leaked or spilled onto hot surfaces or electrical components can cause a fire.
Maintenance Schedule Interval Hours Daily CHECK POINT Every Every Every Every Every 250hrs 500hrs 1000hrs 2000hrs 1000hrs or or or or or a month 3 months 6 months a year 18 months General Maintenance Section Test fuel system for leaks Prior to any service of maintenance activity Inspect engine for fluid leaks O Check engine oil and filter O Change engine oil and filter O Inspect accessory drive belts O Inspect electrical system O Inspect all vacuum lines and fittings O Inspect all fuel fittings and hoses
ENGINE SYSTEM Engine Overview The cylinder blocks are made of the special cast iron and employ 5-bearing, deep skirt system. The cylinder heads have hemisphere combustion chambers, are of cross flow type arranged with V-type valves and high efficient combustion is intended. G424 Service Manual The camshaft is located on the top of the cylinder heads and driven by cog type timing belt. Dual type exhaust manifold is employed in order to reduce output loss by exhaust interference.
Gasoline Engine G424 Service Manual 23 Engine System
LPG Engine ( Low Emission Version) G424 Service Manual 24 Engine System
Timing System The timing belt is meshed with the sprockets, the crankshaft sprocket becomes the drive sprocket, and thus functions to drive the camshaft and oil pump. Timing belt The timing belt is the cogged type, using rubber as its basic material, and it employs a high-strength glass fiber core which does not expand or contract. The features of the cogged-type belt compared to a chin are no expansion/contraction, low noise level, no necessity for lubrication, light weight, etc.
Silent Shaft Mechanism The silent shaft mechanism function mainly to eliminate, by the action of the silent shafts incorporated at both sides of the cylinder block, the vertical vibromotive force of the engine as well as the vibromotive moment in the rolling direction, thus making possible quieter operation of the vehicle. The two silent shafts are arranged as shown in the G424 Service Manual figure below.
Auto Lash Adjuster Construction These engines have auto lash adjusters that eliminate the need for valve clearance adjustment and reduce noises of the valve system. The auto lash adjuster automatically absorbs change in the valve clearance caused by engine temperature change or wear of parts and adjusts the valve clearance always to zero.
Intake and Exhaust System Gasoline Engine The intake manifold employs the shape having good intake performance. The exhaust manifold employs a dual type and intend the reduction of output loss due to exhaust interference.
LPG Engine (Low Emission Version) G424 Service Manual 29 Engine System
Electrical System Wiring Diagram (Gasoline Engine) Stating motor is of the gear reduction type. Distributor is of a breakerless type and employs the ignition advancer which uses jointly centrifugal type and vacuum type.
Wiring Diagram (LPG Engine, Low Emission Version) G424 Service Manual 31 Engine System
STARTING SYSTEM General Description The starting motor is used to turn the engine flywheel fast enough to make the engine run. The starting motor has a solenoid. When the ignition switch is activated, voltage from the electrical system will cause the solenoid to move the pinion toward the flywheel ring gear of the engine. The electrical contacts in the solenoid close the circuit between the battery and the starting motor just before the pinion engages the ring gear. This causes the starting motor to rotate.
1 2 START SWITC.H WH START RELAP W X 3 4 RD/WH MTR BAT STARTER MOTOR BATTERY 5 Typical 12 Volt Starting Circuit (1) Test point. (2) Test point. (3) Test Point. (4) Test Point. (5) Test Point. (X) Hold-in coil. (W) Pull-in coil. Diagnosis Procedure 2. Is a high current switch rated about 1000 amps that actually turns on the starting motor. The following simplified procedure is intended to help the serviceman determine if a starting motor needs to be removed and replaced or repaired.
The result of these switches and relays is to permit a 5 amp dash-mounted switch to turn on a 500 to 1000 amp motor used to crank an engine. If the starting motor cranks real slow or does not crank at all, do the following procedure: 1. Measure battery voltage at the battery posts with the multimeter while cranking or attempting to crank the engine. Make sure to measure the battery posts. Do not measure the cable post clamps.
7. Are all the voltages within specifications ? Start Relay Tests I I If the voltage drops are correct, go to Step 8, to check the engine. D167422 Relay 1. Put the multimeter on the 200 ohm scale. If the voltage drops are too high, repair and/or replace the faulty electrical component. 2. Put the multimeter lead to the 85 and 86 terminals. 8. Rotate the crankshaft by hand to make sure it is not locked up. Check oil viscosity and any external loads that would affect engine rotation. 3.
Starter Motor Planetary Gear Reduction Drive Type The starter motor is small in size light weight and highoutput type. Rotation of the motor are reduced by the reduction gear, and high torque is transmitted to the pinion gear. Operation 1. When the ignition key (IG-SW) is turned to the “ST” position, current flows from the S terminal of the magnetic switch to the pull-in coil and the holding coil.
2. The plunger of the magnetic switch is then attracted, and the pinion is pushed out by the shift lever, meshing with the ring gear. As a result of the movement of the plunger, the contacts of the magnetic switch close, and, as a result, the starter is turned by the high current from the battery directly to the B terminal, and the engine is activated. When the contacts closes, the current flowing to the pull-in coil stops flowing, and the magnetic force decreases.
When the internal gear is fixed as in the case of the starter motor, the carrier rotates in the same direction as the sun gear. This may be used to determine the reduction ratio easily. . Namely, the carrier reduction ratio = (43 + 11) / 11 =. 4.9 Permanent magnet pole Conventionally, the field coil wound around the pole is energized to generate magnetic fluxes. This system uses a permanent magnet (ferrite magnet) for the pole, eliminating the field coil and reducing the size and weight.
Removal and Installation Removal steps 1. Bolt 2. Starter 6EN0867 Inspection Pinion Gap Adjustment (1) Disconnect the field coil wire from terminal M of the magnetic switch. (2) Connect a 12 V battery between terminal S and starter motor body (positive terminal to terminal S). S Caution: This test must be performed quickly (in less than 10 seconds) to prevent the coil from burning out. Stopper Pinion gap Pinion (3) Set switch to “ON”, and pinion will move out.
Pull-in Test of Magnetic Switch S (1) Disconnect field coil wire from terminal M of magnetic switch. (2) Connect a 12V battery between terminal S and terminal M. M Caution: This test must be performed quickly (in less than 10 seconds) to prevent coil from burning. Disconnect connector 6EN0871 (3) If pinion moves out, then pull-in coil is good. If it doesn’t. replace magnetic switch. Hold-in Test of Magnetic Switch (1) Disconnect field coil wire from terminal M of magnetic switch.
Free Running Test Variable resistance M Ammeter Starter motor Battery 12 Voltmeter 6EN0874 (1) Place starter motor in a vise equipped with soft jaws and connect a fully-charged 12-volt battery to starter motor as follows: (2) Connect a ammeter (100-ampere scale) and carbon pile rheostat in series with battery positive post and starter motor terminal. (3) Connect a voltmeter (15-volt scale) across starter motor. (4) Rotate carbon pile to full-resistance position.
Disassembly And Reassembly 6EN1917 A B B G424 Service Manual Disassembly steps 1. Screw 2. Magnetic switch 3. Screw 4. Screw 5. Rear bracket 6. Brush holder 7. Brush 8. Rear bearing 9. Armature 10. Yoke assembly 11. Ball C C 42 A A 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22.
Maguetic switch Disassembly Service Points “S” teminal A “B” terminal “M” terminal Fieldcoid wire 6EN0610 Disconnect the field coil wire from terminal M of the magnetic switch B Armature/ball removal Caution: When removing the armature, take care not to lose the ball (Which is used as a bearing) in the armature end. C Socket Magnetic switch removal Snap ring/stop ring removal (1) Press stop ring off snap ring with a suitable socket.
Inspection 1. Commutator (1) Place the armature on a pair of V-blocks and check the runout using a dial gauge. Standard value: 0.5 mm (0.020 in.) Limit: 0.1 mm (0.004 in.) 1EN0298 (2) Check the outer diameter of the commutator. Standard value: 29.4 mm (1.16 in.) Limited: 28.8 mm (1.13 in.) 1EN0302 (3) Check depth of the undercuts between the segments. Standard value: 0.5 mm (0.020 in.) Limited: 0.2 mm (0.008 in.) Under cut Segment Mica 1EN0296 2.
4. Brush Wear limit line (1) Brushes that are worn beyond wear limit line, or oil soaked, should be replaced. (2) When replacing ground brush, side the brush from brush holder by prying retainer spring back. 1EN0292 5. Armature Coil Short Circuit Test (1) Place armature on a growler. (2) Hold a thin steel blade parallel and just above while rotating armature slowly in growler. A shorted armature will cause blade to vibrate and be attracted to the core. Replace shorted armature. 6EN0600 6.
Reassembly Service Points A Stop Stop ring/snap ring Installation Using a suitable pulling tool, pull overrunning clutch stop ring over snap ring.
CHARGING SYSTEM Alternators General Description The alternators used on these engines have three phase, full-wave, rectified output. They are the brush type. Refer to the Alternator Coverage chart for detailed systems operation information The alternator is an electrical and mechanical components driven by a belt from engine rotation. It is used to charge the storage battery during the engine operation. The alternator is cooled by an external fan mounted behind the pulley.
D187478 Daewoo CS-121 Series 1 1 2 IDES044S IDES043S D167411 Rated voltage..................................................12 volts Polarity is negative ground. Rotation is clockwise. Output at 6500 rpm (cold) .............................61 amps Output voltage ...................................14.0 L 0.5 volts (1) Torque for battery terminal nut.......3.6 L 0.8 NIm (32 L 7 lbIin) (2) Torque for pulley nut ...
Remove & Install Alternator NOTE : Hood, seat and dry air cleaner have been removed for photographic purposes. 2 1 1. Disconnect wire (1) and wire (2) 3 5 4 2. Remove bolt and washer (3), and remove belt (4). 3. Remove alternator (5). NOTE : For the installation of the alternator, reverse the removal steps.
IGNITION SYSTEM Breakerless Ignition System Ignition System Schematic (1) Battery. (2) Ignition switch. (3) Coil. (4) Distributor. (5) Spark Plug. The ignition system has battery (1), ignition switch (2), coil (3), distributor (4) with inner electronics circuits and spark plugs (5). The battery and ignition switch have terminals and closed contacts to permit battery current flow through the ignition system.
Distributor The distributor is the contactless type and is equipped with a centrifugal advancer and vacuum advancer. The distributor is installed at the front side surface of the cylinder head, and is driven directly by the camshaft.
Governor advance mechanism In the figure below, pin A rotates together with the shaft. A governor weight is installed to this pin A. There is a pin B on the governor weight which fits into the oblong hole in the cam base. The governor spring is attached to the spring hook of the governor weight, pulling the governor weight to the fully closed position. When the rotation speed increases, the governor weight is subjected to centrifugal force which causes it to open outward.
Vacuum advance mechanism There is a diaphragm within the vacuum controller, with a spring at the negative-pressure (vacuum) side which pressure against the diaphragm. A link is attached to the diaphragm and is connected to the pickup plate. The pickup assy is installed on the pickup plate, and can rotate together with the pickup plate. The negative pressure (vacuum) side of the vacuum controller is connected to the vacuum port of the carburetor by a tube.
Removal and Installation Removal steps 1. Drive belt 2. Water pump pulley 3. Crankshaft pulley 4. Spark plug cable 5. Spark plug 6. High tension cable G424 Service Manual A 54 7. Vacuum 8. Ignition 9. Harness 10.
Inspection High voltage terminal Ignition Coil Perform the following measurements. Replace the ignition coil if the standard values are not met. – + 1EN0393 (1) Measure the resistance values of the primary and secondary coils and of the external resistor with a tester. If the readings are within the standard limits, it follows that there is no short or open circuit in the ignition coil. Standard value: Primary coil resistance value: 1.08 to 1.32 Ω Secondary coil resistance value: 22.1 to 29.
Disassembly and Reassembly A G424 Service Manual Disassembly steps 1. Distributor cap 2. Rotor 3. Cover 4. Signal rotor 5. Pickup coil assembly 6. Ignitor 7. Heat sink 8. Breaker assembly 9. Snap ring 10. Vacuum control 11. Connector assembly 12. O-ring 13.
Inspection Pickup Coil (1) Using a tester, check the resistance of the pickup coil. Standard value: 420 to 540Ω 1EL0052 (2) Check to make sure the pointer of the tester oscillates when the tip of a screwdriver is moved past by the core of the pickup col assembly. 1EL0053 Signal rotor Reassembly Procedure A Pickup coil assembly installation Check the air gap between the signal rotor and pickup assembly. Standard value: 0.35 to 0.45 mm (0.0138 to 0.0177 in.
GASOLINE FUEL SYSTEM General Description The fuel pump pulls the fuel from fuel tank. The fuel flows through filter, which is installed on top of the fuel tank, to carburetor where the fuel is mixed with air at the correct ratio. This air and fuel mixture then goes to the inlet manifold. The air and fuel mixture takes in heat and is completely changed to vapor as it goes through the inlet manifold to the combustion chamber of each cylinder.
Gasoline Carburetor - Operation Construction of Carburetor (1) Float. (2) Front chamber cover. (3) Primary inner venturi. (4) Choke valve. (5) Accelerator pump nozzle. (6) Idle compensator. (7) Membrane cover. (8) Enrichment jet. (9) Plug. (10) Throttle body. (11) Primary throttle valve. (12) Mixture adjusting screw. (13) Bypass screw. (14) Primary main jet. (15) Body. (16) Pump inlet ball. (17) Pump lever. (18) Fuel cutoff solenoid. (19) Pump outlet ball. (20) Primary pilot jet. (21) Valve weight.
1. Air system Air passed through the air cleaner flows through the choke bore and venturi into the clearance of the throttle valve and supports idle running of the engine. When engine speed increases to off-idle and more, intake air is metered by the venturi. Air flow to be fed to the cylinders is controlled by the throttle valve. 2. Float system Float System G424 Service Manual The float maintains a constant fuel level in the float chamber.
3. Idle system This system provides adequate air-fuel-mixture richness for smooth engine running ranging from slowidle to light-load operation. Fuel from the float chamber is sent through the main jet to the pilot jet where metering of fuel is made. On the other hand, air entering the venturi air leak and that entering the pilot air jet No.2 join at the pilot air jet No.1 where metering of air is made.
Idle Compensator Main Metering System The idle compensator uses a bimetal. When the carbretor ambient temperature rises during idle or “off idle” running, the bimetal bends enough to open the compensator valve. Now additional air from the choke bore can flow through the auxiliary air passage to the intake manifold directly. It leans out the mixture enough to make up for the proper richness. Fuel metered by the main jet is bled by air from the main air jet and enters the bleed pipe through its holes.
5. Enrichment system Enrichment and Accelerator-Pump systems The enrichment system provides additional fuel feed to the main metering system during highspeed large-torque operation. This system use the membrane (diaphragm) which is actuated by the intake manifold vacuum and membrane spring to open or close the fuel feed line.
Removal and Installation 6EN1893 A G424 Service Manual Removal steps 1. Return set hose assembly 2. Oil seal 3. Air horn 4. Gasket 5. Carburetor 6. Air governor 7. Gasket B 64 A 8. Fuel pipe 9. Fuel hose 10. Fuel pipe 11. Fuel pump 12. Gasket 13. Insulator 14.
Removal Service Points A Carburetor removal (1) Hold the carburetor in a level position while using care not to let fuel spill, remove it from the intake manifold. (2) Turn the carburetor upside down on a pan to drain fuel. B Fuel pump removal Placing the piston in No.1 cylinder at TDC on the compression stroke makes the fuel pump stroke lift the smallest, allowing easy removal of the pump.
Gasoline Carburetor Disassembly and Reassembly A A B C C C C D B B A Disassembly steps 1. Throttle return spring 2. Damper spring 3. Choke rod 4. Screw 5. Float chamber cover 6. Float chamber cover gasket 7. Cover 8. Packing 9. Bimetal 10. O-ring 11. Accelerator wire bracket 12. Float pin 13. Float 14. Needle valve assembly 15. Packing 16. Filter 17. Weight 18. Ball 19. Main jet 20. Screw 21. Screw 22. Accelerator pump cover 23. Diaphragm 24. Spring 25. Fuel cut solenoid 26. O-ring 27. Enrichment 28.
Service Points of Disassembly The following parts must not be disassembled at the time of disassembly. (1) Choke valve and choke shaft (2) Inner venturi (3) Throttle valve and throttle shaft A Return spring/choke rod removal (1) When the spring is removed, avoid prying it with undue force or any other attempt that can cause damage to it. (2) Press the end of the choke rod to force the rod out. Avoid applying a strong force to the plastic grommet of the rod fit-in hole.
Inspection 1. General Inspection Check the following and repair or replace parts if faulty. (1) Check fuel passages (jets) and air passages (jets or orifices) for clogging. If clogged, wash thoroughly with cleaning solvent or detergent and remove dirt by compressed air. Do not use wire or other metal pieces. (2) Check diaphragms, O-rings and springs for damage and cracks. (3) Check that needle valve operates lightly. If the valve is hard to operate or is binding, repair or replace.
4. Inspection of Mixture Adjusting Screw (MAS) Check tapered end of mixture adjusting screw (MAS) for damage from over tightening, etc. Check for damage 6EN1888 5. Throttle Body Check Make sure that the throttle shaft moves smoothly. If any sticky movement is found, thoroughly clean the shaft, and then coat it with a small amount of engine oil. Do not disassemble the shaft unnecessarily.
(2) Main jets have size symbols stamped on their ends for identification. Size symbols : 132.5 132.5 Size symbol 6EN0869 B Weight Check ball Check ball/weight installation Install the acceleration check ball and weight. C Float/float pin installation After the float and float pin have been installed, make sure that the float is in a level position.
Choke shaft Inspection and Adjustment After Reassembly Choke lever 1. Fast Idle Opening (1) Move the choke lever to place the choke valve in fully closed position. 6EN0859 (2) Measure the clearance “A” (primary throttle valve to throttle bore). Primary throttle valve NOTE: Refer to the table in SERVICE SPECIFICATIONS for the clearance.
3. Ports (1) Connect a hand vacuum pump and check each port for clogging. (2) If clogged, clean the port and then blow air into it.
LP FUEL SYSTEM General Description Electric Fuelock Model 3 6 2 7 . 3 2 1 1 4 5 IDES061P 5 6 LP Fuel System Components (1) Converter. (2) Fuelock. (3) Carburetor. (4) Coolant ontlet line (5) Coolant inlet line. (6) Balance hose. (7) LP fuel line to carburetor 7 IDES062S engine coolant that flows in line (5) and out line (4). Carburetor vacuum activates the converters operation and the fuel flows to the carburetor through line (7).
Electric Fuelock Converter Fuelock (2) is electrically activated by an oil pressure switch. When the engine is stopped, or if the engine oil pressure gets lower than the pressure for operation, the oil pressure switch will open. When the oil pressure switch opens, it will close the fuelock, which stops the supply of fuel to the converter. 2 3 4 1 5 6 Fuel Filter 7 8 IDES064P 8 Converter Components (1) LP fuel inlet opening. (2) Primary regulator valve. (3) Primary valve pin. (4) Fulcrum.
The converter is a combination regulator and vaporizer. It receives liquid fuel through opening (1) at tank pressure from the fuelock. The fuel is available inside converter vaporizing chamber (9) when carburetor vacuum is felt in converter opening (8). When vacuum is not available at the fuelock or opening (8), primary valve pin (3) puts force on primary regulator valve (2) that makes a seat against an inner passage for the fuel inlet.
valve (2) measures the air flow that goes into the engine, respective to the demands of the engine and throttle valve (10) position. The air pressure drop of 1.3 to 2.7 kPa (0.2 to 0.4 psi) is controlled by metering spring (4) which permits the force necessary to pull in the fuel into the air flow. LP gas metering valve (6) is connected to the air valve and lets in the correct amount of fuel from the LP converter to mix with the air at any opening of the air valve.
1. Make sure the setting for ignition timing is correct. Tests or Adjustments See Ignition Timing. Adhere to the following warnings when performing any tests or adjustments while the engine is running. 2. Connect the Electrical System Analyzer as shown in Engine RPM Check in the Testing And Adjusting. WARNING 3. Start and run the engine until the engine reaches normal operating temperature. Work carefully around an engine that is running.
Power Mixture Adjustment CO Meter Method The method of adjustment depends upon the test equipment that is available. The power mixture can be adjusted using a CO meter, vacuum gauge or electrical system analyzer. The CO meter method is the preferred method for reduced emissions. The vacuum gauge method is the next most accurate method if CO measuring equipment is not available. The engine speed method is the easiest but least accurate method.
Inner Fuel System Leak Check Fuel System Leak Check Outer Fuel System Leak Check 3 2 1 WARNING LP gas is highly flammable. To prevent personal injury, keep fire and flammable materials away from the lift truck when work is done on the fuel system. Combustion gases from LP gas fuel system can be a danger. To find LP gas leaks, use soap and water solution or other foaming bubble solvent around fuel line connections and on other components that possibly cause LP gas leaks.
Converter Leak Test 6 7 To check the converter for leakage after repair, do the procedure that follows: 8 1. Put a plug in the fuel outlet openings. 9 10 2. Put compressed air in the fuel inlet openings, up to a maximum of 725 kPa (120 psi). 3. Wait ten minutes and then check the converter or fuelock for air leaks. Listen for air to come out around gaskets or seals. IDES106P Carburetor Components (Carburetor Shown Removed For Better Illustration) (6) Spring. (7) Backup plate and diaphragm.
LP Converter - Check, Clean Test LP-Gas Converter 1. Obtain a test kit. 2. Start engine. 3. Close the liquid outlet valve in the fuel storage container. 4. Run engine out of fuel. 5. Install the 0-30kPa (0-5 psi) gauge in the primary test port. Secondary Test Port 6.. Install the 0-2.5kPa (0-10 in H O) gauge in the secondary test port. Primary Test Port 2 LP-Gas Converter 7. Slowly open the liquid outiet valve in the fuel storage container. Inspect Converter for Oil Accumulation 8. Start the engine.
Disassembly & Assembly LPG Carburetor Remove & Install LP Gas Carburetor 6EN1890 Removal steps 1. Throttle return spring 2. Accel wire assembly 3. Return spring support 4. LPG carburetor 5. Throttle chamber gasket G424 Service Manual 6. Throttle body 7. Carburetor gasket 8. Air governor 9. Air governor gasket 10.
Disassemble LP Gas Carburetor 9 Start By: 10 a. Remove LP Gas Carburetor. 11 2 P0004825 8 1 4. Remove power mixture screw (8), idle mixture screw (9) and the spring. Remove four screws (10). Remove throttle body assembly (11) and the gasket. P0004821 1. Remove four screws (1) and cover (2). 4 12 P0003003 3 P0004822 5. Remove gasket (12). 2. Remove spring (3). Remove diaphragm assembly (4). 5 5 6 16 6 13 14 15 7 P0004829 P0003001 6. Remove nut (13). 7.
Assemble LP Gas Carburetor LP Gas Fuelock Remove & Install LP Gas Fuelock 1 16 13 14 15 3 P0004829 2 1. Check all parts for damage. Replace damaged parts with new as necessary. P0002926 2. Make sure all parts are clean and free of dirt and foreign material. 1. Disconnect fuel lines (1). 3. Put throttle shaft (17) in position in the throttle body, and install stop lever (16). 2. Disconnect wire (2). 3. Remove fuelock (3). 4. Put throttle plate (15) in position and install the two screws.
Disassembly of LP Gas Converter LP Gas Converter Remove & Install LP Gas Converter 1 Start by : Remove LP Gas Fuelock. 1 3 2 IDED048P 3 1. Remove six screws (1), cover (2), and diaphragm (3) from the converter. 2 P0004817 4 1. Remove lines (1). 5 2. Remove two bolts and nut (2). 3. Remove LP gas converter (3). NOTE : For the installation of the LP gas converter, reverse the removal steps.
10 IDED051P 4. Remove spring and plunger (10) from the intermediate cover. 13 11 12 IDED052P 1. Screw (6) 5. Remove intermediate cover (11), diaphragm (12) and the secondary regulator valve (13). 2. Cover Assembly, Secondary 3. Diaphragm Assembly, Secondary Inspection, Assembly of LP Gas Converter 4. Screw, 1. Clean primary and secondary valves with soap and warm water and inspect for wear. Replace if required. 5. Lever, Secondary 6. Pin, Secondary Fulcrum 7. Seat, Secondary 2.
LPG FUEL SYSTEM (LOW EMISSION VERSION) General Description Air cleaner (MAP) Schematic of G424 LP fuel system (low emission version) G242 LP engine (Low Emission Version) is different from standard G424 LP engine. To reduce emission of exhaust gas, closed loop carburetion system and catalytic muffler are applied to low emission version G424 LP engine. regulate the air/fuel mixtures, correcting for proper air/fuel.
FUELOCK VALVE LP CONVERTER LP CARBURETOR GOVERNER MUFFLER ENGINE Open-loop LP Carburetion System : G424 LP engine TACHO SENSOR INTAKE BOOST FUEL CONTROL VALVE ENGINE CONTROL UNIT (ECU) OXYGEN SENSOR FUELOCK VALVE LP CONVERTER LP CARBURETOR GOVERNER CATALYTIC MUFFLER ENGINE Closed-loop LP Carburetion System : G424 LP engine (low emission version) G424 Service Manual 88 LPG Fuel System(Low Emission Version)
ports (9) in the air valve (3). A pressure / force imbalance begins to build across the air valve diaphragm (5) between the air valve vacuum chamber (8) and atmospheric pressure below the diaphragm (10). LP Carburetor (Variable Venturi) The variable venturi air/fuel mixer is mounted in the intake air stream between the air cleaner and the intake manifold. The design of the main section incorporates a cylindrical bore through the center (1) and a gas discharge jet (2).
Vacuum Switch (MAP) Vacuum Switch 1 2 3 1. Electrical 2. Vacuum port 3. Main body 1. Electrical 2. Vacuum port 3. Main body The vacuum switch is a simple direct acting contact pressure switch, consisting of a main body (3), an electrical connector with two pins (1) and a vacuum port connection (2). The unit is normally open (i.e. the electrical connectors (1) are not common) when no vacuum is applied to the vacuum port (2).
chamber and the primary atmospheric chamber (18) This causes the primary diaphragm and lever assembly (9) to pivot (10) against primary spring (3) pressure, raising primary valve pin (11), closing off the primary valve (2). Since fuel pressure falls from tank pressure, a liquid liquefied petroleum gas evaporates. As this phase change occurs the fuel takes on heat from the primary heat exchanger chamber of the regulator (4).
Fuel Control Valve Fuel Lock - Off 2 3 1 6EV2142 6EN2139 1. 2. 3. 4. Carburetor AVV port connection Vaporizer secondary vent chamber connection Electrical connectors Balance line connection 1. 2. 3. 4. The fuel control valve is a three way valve, operated by a pulse width modulated electronic signal applied to the electrical connectors (3) by the fuel system ECU.
Engine Control Unit (ECU) 6EV2149 In order to obtain maximum emission reductions from the exhaust gas catalyst, accurate control of the engines operating air fuel ratio (AFR) is required. The engine control unit (ECU) uses input from three sources: excess oxygen information from the exhaust gas oxygen sensor (EGO), ignition pulses (engine RPM) and intake manifold pressure (high or low). This input is used to apply a duty cycle and a rate of change of that duty cycle to the fuel control valve (FCV).
Oxygen Sensor Cover Connector Housing Lead wire Sensor device 6EN2146 The oxygen sensor installed on the exhaust manifold makes use of the principles of a solid electrolyte oxygen concentration cell. The oxygen concentration cell is characterized by a sharp change of the output voltage in the vicinity of the stoichiometric air/fuel ratio.
Catalytic Muffler Performance of Three-Way Catalytic Converter Operating window for converter The catalytic muffler is mounted in the exhaust gas stream of G430 engine. The catalytic muffler facilitates oxidation and reduction reactions that reduce the amount of unwanted constituents in the exhaust gas stream. Catalytic mufflers have sound deadening and spark arresting features incorporated into the design.
Tests or Adjustments Adhere to the following warnings when performing any tests or adjustments while the engine is running. WARNING Work carefully around an engine that is running. Engine parts that are hot, or parts that are moving, can cause personal injury. 9. When reassembling mixer, locate the notch on air/gas valve diaphragm to point to fuel inlet. 10. Open the fule storage container liquid outlet valve solwly. WARNING 11. Check for leaks.
LP Converter-Check, Clen Inspection of Vacuum Switch See, “LP Converter-Check, Clean” in LP Fuel System Section. Inspection of Fuel Lock - Off 6EN2132 1. Connect a hand vacuum pump to the nipple of the vacuum switch. 6EN2135 2. Using a vacuum pump, vacuum (0.7 or more kPa) is applied to a vacuum sensor, and the existence of continuity between sensor terminals is checked. 1. When voltage is impressed to the terminal of fuel lock-off, check whether there si operation sound. Vacuum gauge Not applied 0.
Inspection of Oxygen Sensor Blue code White code Oxygen sensor side (1) Before checking, warm up the engine until engine coolant temperature reaches 80 to 95°C (2) In the state where engine is poerated disconnent the oxygen sensor connector and connect a voltmeter. Caution The right measurement cannot be pertormed if oxygen sensor connector is separated before engine starting (3) Measure the oxygen sensor output voltage. Standard value : 0.6 - 1.
Disassembly & Assembly LPG Carburetor Removal and Installation of LP Gas Carburetor 7 6EN2143 Removal steps 1. Bracket - Accel Wire 2. LPG Carburetor 3. Carburetor Gasket 4. Air Governor 5. Governor Gasket 6. Fuel pump Cover 7.
Disassembly & Assembly of LP Gas Carburetor 6EN2147 Removal steps 1. Bolt 2. LPG mixer 3. Gasket 4. Vacuum switch 5. Fitting 6. Vacuum switch (MAP) 7. Idle adjustment screw 8. Idle adjustment screw spring 9.
LP Gas Converter Removal & Installation of LP Gas Converter 6EN2148 Removal steps 1. 2. 3. 4. 5. 6. 7. 8. 9. Vacuum terminal 10. Balance hose 11. Jet 12. Elbow fitting 13. Elbow fitting 14. Fuel outlet plug 15. Bolt washer assembly 16. Converter Vacuum hose Vacuum hose Vacuum hose Fuel control valve LPG shut off valve assembly Balance hose Check valve elbow fitting Balance hose Disassemble & Assemble of LP Gas Converter See, “Disassembly & Assembly” of LP Fuel System Section.
DUAL FUEL SYSTEM 1 2 3 5 4 6 7 8 9 10 11 12 13 14 IDES071S Dual Fuel Basic Schematic (1) Gasoline inlet line (from gasoline tank). (2) Mechanical fuel pump. (3) LP mixer. (4) Balance hose. (5) LP electric fuelock. (6) LP fuel line. (7) Gasoline electric fuelock. (8) Converter. (9) Selector switch. (10) Carburetor. (11) Elbow. (12) LP fuel line. (13) LP fuel filter. (14) LP fuel inlet line (from LP tank).
GOVERNING SYSTEM General Description Sectional View of Air Governor (1) Body. (2) Stabilizer rod. (3) Stabilizer piston. (4) Throttle plate. (5) Throttle plate shaft. (6) Bearing. (7) Nipple. (8) Spring. (9) Bush nut. (10) Adjusting screw. (11) Plate. (12) Cam The air governor is located to the underside of the carburetor. It serves to protect the hydraulic pump, to limit the maximum traveling speed of the vehicle, and to prevent excessive increase of engine speed. 2.
Air Governor Disassembly and Reassembly 6EN0862 A A A B Disassembly steps 1. Ventilation hose 2. Gasket 3. Sealing cap 4. Cover plate assembly 5. Gasket 6. Adjusting nut 7. Adjusting screw 8. Plate assembly 9. Valve assembly 10. Valve shaft assembly 11. Piston cover 12. Gasket 13. Stabilizer piston 14. Piston shaft 15.
Inspection Piston shaft Stabilizer piston Valve 1. Check the plate assembly (8) composed of a ribbon spring and coil spring for cracks and any other damage. 2. Check the valve shaft for wear, and also make sure that it rotates smoothly when mounted in the body. 3. Check the piston for damage. Check also the valve fit-in section of the shaft for damage. 4. Grease packed needle bearings are press-fitted at both ends of the valve shaft hole of the governor body.
LUBRICATION SYSTEM General Description Cam shaft Oil pressure switch Oil filter Crankshaft Oil pump Oil pan Oil pickup Lubricating system is the full-flow filtered pressurefeed oil system and the oil reserved in the oil pan is fed with pressure to each part of engine. After the oil pressure is adjusted through the relief valve, the oil is fed to the cylinder blocks and cylinder head. In the cylinder head the oil is forcibly fed to the camshaft journals, rocker arm pivots and further cam surfaces.
NOTE : In normal case, the recommended engine oil for G424 engine is SAE 10W - 30. Testing & Adjusting Adhere to the following warnings when performing any tests or adjustments while the engine is running. But, if the excessive valve noise occurs up to five minutes after a cold start and if the maximum ambient temperature is lower than 10°C (50°F), it is recommended to change engine oil to SAE 5W - 30 for that application. WARNING Work carefully around an engine that is running.
NOTE: Too much oil consumption can also be the result if oil with the wrong viscosity is used. Oil with a thin viscosity can be caused by fuel leakage into the crankcase, or by increased engine temperature. When some components of the engine show bearing wear in a short time, the cause can be a restriction in an oil passage. A broken oil passage can also be the cause.
Oil Pressure Check 2 1 Oil Pressure Check (1) LP pressure switch. (2) Oil pressure switch. (two-terminals) (one-terminal) 1. With the engine OFF, make sure the oil level is correct. Connect the analyzer to the engine as shown in Engine RPM Check in the Testing And Adjusting. WARNING Before the LP/oil pressure switch is removed, the engine must be stopped. Make sure oil pressure is released to prevent personal injury. 2. Remove LP pressure switch (1) or oil pressure switch (2).
COOLING SYSTEM General Description 1 2 5 3 6 8 7 9 10 Cooling System Schematic (1) Cylinder head. (2) Thermostat. (3) Recovery tank. (5) Radiator top hose. (6) Radiator pressure cap. (7) Cylinder walls. (8) Radiator. (9) Radiator lower hose. (10) Water pump. Water pump (10) is installed on the front of the cylinder block. The water pump is driven by a single V belt from the crankshaft pulley. The inlet opening of the water pump is connected to the radiator lower hose (9).
Testing & Adjusting 4. Look for bent radiator fins. Be sure that air flow through the radiator does not have a restriction. Adhere to the following warnings when performing any tests or adjustments while the engine is running: 5. Inspect the drive belts for the fan. 6. Check for damage to the fan blades. WARNING 7. Look for air or combustion gas in the cooling system. Work carefully around an engine that is running. Engine parts that are hot, or parts that are moving, can cause personal injury. 8.
Pressure Cap Test Cooling System Leak Check To test the cooling system for leaks, use the following procedure: A WARNING If the engine has been in operation and the coolant is hot, slowly loosen the pressure cap to the first stop and let the pressure out of the cooling system, then remove the pressure cap. 1. Remove pressure cap from the radiator. 2. Make sure the radiator is full (hot) or nearly full (cold) of coolant. IDES109S Pressure Cap Diagram (A) Sealing surface of cap and radiator. 3.
Thermostat The thermostat is the wax pellet type. A jiggle valve (which improves air bleeding during water supply) is provided on the flange part. When the thermostat is closed, the circulation of coolant is stopped, thereby making warm-up faster. When the temperature increases further and reaches a certain specified temperature, the valve opens fully, allowing even more coolant to circulate through the radiator.
Cooling System Heat Problems Cooling System Recommendation To check if there is a good reason for heat problems do the checks that follow: Coolant Information 1. The indications of a heat problem are as follows: a. High coolant temperature indicator light is on or needle of coolant temperature gauge is in red range. b. Coolant boils out (comes out because of too much heat) of the cooling system during operations. c. Coolant boils out on the floor when the engine is stopped. d.
Coolant Water DAEWOO recommends selecting automotive antifreeze suitable for gasoline engines using aluminum alloy parts. The antifreeze should meet ASTM-D3306 standard. Hard water, or water with high levels of calcium and magnesium ions, encourages the formation of insoluble chemical compounds by combining with cooling system additives such as silicates and phosphates. Make proper antifreeze additions.
Belt Adjustment V-Belt Diagnosis Belts and pulleys wear evenly with use. Unusual signs of wear indicate some correction is needed. The correction of any of the listed conditions will help extend belt life. Drive belts must grip the entire contact area of the pulley. When drive belts are too loose, the belts can slip, tear, burn, or grab and snap. More belts fail from being too loose than too tight.
Gouged Edge Service Procedures A gouged edge in a belt can be caused by a damaged pulley, a misaligned pulley, or the belt being too loose or too long. Check the pulley and the belt for proper alignment and tension. Make sure other components are not misaligned and rubbing against the belt. Draining and Filling the Cooling System Various methods and equipment can be used. Worn Sides Draining Belts that are worn on the sides are probably too loose. The pulley may also be misaligned.
Filling Radiator Service 1. Check the radiator drain cock to be sure it is closed. Radiator Internal Deposits 2. Check the engine drain plug to be sure it is tight. A radiator with a dirty, obstructed, or leaking core will cause the engine to overheat. A scale deposit inside the radiator is a result of using hard, high mineral content water in the cooling system.
Remove & Install Water Temperature Sender 1 2 1. Disconnect one wire connection (1). 2. Remove water temperature sender (2). NOTE: For the installation of the water temperature sender, reverse the removal steps. 3. Use thread sealant on the water temperature sender threads.
BASE ENGINE SERVICE PROCEDURE Timing Belt Removal and Installation A B C H G G G F E D G424 Service Manual Removal steps 1. Timing belt front cover upper 2. Timing belt front cover lower 3. Timing belt 4. Tensioner spacer 5. Tensioner spring 6. Tensioner pulley 7. Oil pump sprocket 8. Crankshaft bolt 9. Crankshaft washer 10. Crankshaft sprocket 11. Flang E F D C G B H 120 A 12. Tensioner B 13. Timing belt B 14. Counterbalance shaft sprocket 15. Spacer 16. Crankshaft sprocket B 17.
Removal Service Points A 6EN0716 Timing belt removal (1) When the timing belt is to be re-used, make an arrow mark on the back surface on the belt to indicate the rotating direction with a chalk or the like so that the belt can be installed in the same direction. (2) Move the timing belt tensioner upward and temporarily tighten the tensioner lock bolt. (3) Remove the timing belt. 6EN0884 B Screw driver Oil pump sprocket removal (1) Remove the plug on the left side of cylinder block.
D Crankshaft sprocket removal MD998778 (1) If it is difficult to remove the sprocket, use the special tool. 6EN0642 E Timing belt “B” removal (1) Make a mark on the back of the timing belt indicating the direction of rotation so it may be reassembled in the same direction if it is to be reused. NOTE: Water or oil on the belt shortens its life drastically, so the removed timing belt, sprocket, and tensioner must be free from oil and water. These parts should not be washed.
H MB990767 Crankshaft sprocket removal (1) Using the special tool show in the illustration, lock the camshaft sprocket in position. (2) Loosen the camshaft sprocket bolt. MD998719 6EN0668 Inspection 1. Timing Belt Replace belt if any of the following conditions exist. (1) Hardening of back rubber. Back side is glossy without resilience and leaves no indent when pressed with fingernail. 8EN0066 Cracks Peeling Cracks (2) (3) (4) (5) Cracks Cracks Cracks Cracks on rubber back. or peeling of canvas.
(7) Abnormal wear on teeth Earlier stage: Canvas worn (canvas fibers napped, rubber lost, discolored whitish, and unclear canvas texture) Latter stage: Canvas lost, rubber exposed (tooth width thinner) (8) Missing tooth Rubber exposed Tooth missing 8EN0068 Installation Service Points A Camshaft sprocket installation (1) Using the special tools show in the illustration, lock the camshaft sprocket in position. (2) Tighten the camshaft sprocket bolt to the specified torque.
D Timing marks (on fron case) timing marks Timing belt “B” installation (1) Align timing mark on the crankshaft sprocket “B” and counterbalance shaft sprocket with the marks on the front case respectively. (2) Install the timing belt “B” on the crankshaft sprocket “B” and counterbalance shaft sprocket. There should be no slack on the tension side. DEN0602 (3) Make sure that the relationship between the tensioner pulley center and the bolt center is as shown in the illustration.
E Crankshaft bolt installation (1) Using the special tool, hold the flywheel. (2) Install the crankshaft pulley in position. MD998781 6EN0634 F Oil pump sprocket installation (1) Insert a phillips screwdriver (shank diameter 8 mm[0.31 in.] shaft) through the plug hole on the left side of the cylinder block to the left counterbalance shaft. (2) Install the oil pump sprocket. (3) Apply a proper amount of engine oil to the bearing surfaces of the nuts. (4) Tighten the nuts to the specified torque.
(2) Align the timing mark on the crankshaft sprocket with that on the front case. Timing mask 6EN0671 (3) Align the timing mark on the oil pump sprocket with its mating mark. Timing mark 6EN0672 Tensioner spacer 6EN0015 Timing mark (4) Install the timing belt on the crankshaft sprocket, oil pump sprocket and camshaft sprocket in that order. There should be no slack on the tension side.
(8) Apply force to the tensioner in the direction shown by arrow to make the belt engage completely with each sprocket. Tensioner 6EN0017 (9) Tighten the tensioner attaching bolt to the specified torque. (10) Tighten the tensioner spacer to the specified torque. Tensioner spacer NOTE: If the nut is tightened first, the tensioner may also turn together with the nut and loose tension of the belt may result.
Intake Manifold Removal and Installation 6EN1894 Removal steps 1. Water outlet 2. Gasket 3. Thermostat G424 Service Manual 4. Engine hanger 5. Intake manifold 6.
Exhaust Manifold and Water Pump Gasoline/LPG Engine Removal and Installation 6EN1895 Removal steps 1. Oil level gauge 2. Oil level gauge guide 3. O-ring 4. Heat protector A 5. Heat protector B 6. Engine hanger G424 Service Manual A A 130 7. Exhaust manifold 8. Gasket 9. Water inlet pipe 10.O-ring 11. Water hose 12. Water pump 13.
A O-ring and water pipe installation Replace the water inlet pipe O-ring with a new one. Apply water to the outer circumference of the O-ring for easier insertion into the water pump and thermostat housing. Caution: 1) Never apply engine oil or any other oil or grease to the Oring. 2) Fasten the water pipe after the thermostat housing has been installed.
LPG Engine (Low Emission Version) Removal and Installation T=4.5(32.5)[45] Removal steps 1. Oil level gauge 2. Oil level gauge guide 3. O-ring 4. Heat protector A 5. Heat protector B 6. Oxygen sensor 7. Engine hanger G424 Service Manual A A 132 8. Exhaust manifold 9. Gasket 10. Water inlet pipe 11.O-ring 12. Water hose 13. Water pump 14.
Rocker Arms And Camshaft Removal and Installation 6EN1896 G A G424 Service Manual Removal steps 1. Breather hose 2. P.C.V. hose 3. P.C.V. valve 4. Oil filler cap 5. Rocker cover 6. Gasket 7. Semi-circular packing 8. Rocker arms and rocker shafts 9. Rear bearing cap 10. Rear arm D 11. Spring 133 D D D C B B E F A 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. Bearing cap No. 4 Rocker arm C Bearing cap No. 3 Bearing cap No.
Removal Service Points MD998443 A Rocker arm and rocker shaft removal Caution: If the lash adjuster is re-used, clean the lash adjuster. 6EN0569 (1) Fit the lash adjuster onto the rocker arm without allowing diesel fuel to spill out. Fit. Special tool MD998443 to prevent the lash adjuster coming free and falling to the floor. Inspection 1. Camshaft Measure the cam height and if the limit is exceeded, replace. Standard value: 41.62 mm (1.6386 in.) Limit: 41.12 mm (1.6189 in.) 9EN0058 2.
(2) Place the lash adjuster in container A and clean its outside surface. NOTE: Use a nylon brush if deposits are hard to remove. Diesel fuel 6EN1699 (3) While gently pushing down the internal steel ball using special tool MD998442, move the plunger through five to ten strokes until it slides smoothly. In addition to eliminating stiffness in the plunger, this operation will remove dirty oil.
(6) Remove the lash adjuster from the container. Then, push down the steel ball gently and push the plunger to eliminate diesel fuel from the pressure chamber. MD998442 Diesel fuel 6EN1809 (7) Place the lash adjuster in container C. Then, gently push down the internal steel ball using special tool MD998442. Caution: Do not use container C for cleaning. If cleaning is performed in container C, foreign matter could enter the pressure chamber when the chamber is filled with diesel fuel.
Installation Service Points A Camshaft installation Apply engine oil to the journals and cams of the camshafts. Install the camshaft on the cylinder head. B Notch Rocker shaft installation Insert the rocker shafts into the front bearing cap so that the notches on the shafts face up, and insert the installation bolts without tightening them. Frout bearing cap 6EN0575 C Wave washer Wave washer installation Install the wave washer in correct direction as shown. Front bearing cap No.
E MD998443 Lash adjuster installation Caution: If the lash adjuster is re-used, clean the lash adjuster. (1) Set special tool MD998443 to prevent the lash adjuster coming free and falling to the floor. 6EN0569 F Camshaft oil seal installation (1) Apply engine oil to the lip area of the oil seal and the camshaft front end outer diameter. (2) Using special tool, install the camshaft oil seal.
Cylinder Head And Valves Removal and Installation 6EN1897 A B D C B B C B G424 Service Manual Removal steps 1. Cylinder head bolt 2. Cylinder head assembly 3. Cylinder head gasket 4. Retainer lock 5. Valve spring retainer 6. Valve spring 7. Intake valve 8. Retainer lock 9. Valve spring retainer 10. Valve spring 139 C A C A 11. Exhaust valve 12. Valve stem seal 13. Valve spring seat 14. Valve stem seal 15. Valve spring seat 16. Intake valve guide 17. Exhaust valve guide 18.
Removal Service Points A MB991654 Cylinder head bolt removal Using special tool, loosen the cylinder head bolts. Loosen each bolt evenly, little by little, by two or three steps. 6EN0717 B MD998772 Retainer lock removal Store removed valves, springs and other parts, tagged to indicate their cylinder No. and location for reassembly. 6EN0652 C Valve stem seal removal Caution: Do not reuse removed valve stem seal. Inspection 1.
2. Valve Valve seat contact Margin 6EN0542 (1) Check the valve face for correct contact. If incorrect, reface. Valve seat contact should be maintained uniform at the center of valve face. (2) If the margin exceeds the service limit, replace the valve: Standard value: Intake 1.2 mm (0.047 in.) Exhaust 2.0 mm (0.079 in.) Limit: Intake 0.7 mm (0.028 in.) Exhaust 1.5 mm (0.059 in.) (3) Measure the valve’s total length. If the measurement is less than specified, replace the valve. Standard value: Intake 106.
Valve stem end Valve Projection Spring seating surface 5. Valve Seats (1) Assemble the valve, than measure the valve stem projection between the end of the valve stem and the spring seating surface. If the measurement exceeds the specified limit, replace the valve seat. Standard value: 42.05 mm (1.6555 in.) Limit: 42.55 mm (1.6752 in.) DEN0212 0.9 (0.0 to 1.3 35 t o 0. 05 Unit : mm(in) 1) 60˚ Valve Seat Reconditioning Procedure ) o 1.3 .051 0.9 0t 35 to 0 (0. 60˚ 25˚ 43.
Valve Guide Replacement Procedure (1) Using a press, remove the valve guide toward the cylinder block side. (2) Rebore the valve guide hole to the new oversize valve guide outside diameter. NOTE: Do not install a valve guide of the same size again. Valve guide hole diameter. 0.05 O.S. 13.05 to 13.07 mm (0.5138 to 0.5146 in.) 0.25 O.S. 13.25 to 13.27 mm (0.5217 to 0.5224 in.) 0.50 O.S. 13.50 to 13.52 mm (0.5315 to 0.5323 in.) Press (3) Press in the valve guide to the position shown in the illustration.
C MD998772 Retainer lock installation The valve spring, if excessively compressed, causes the bottom end of the retainer to be in contact. 6EN0652 D Cylinder head bolt installation (1) When installing the cylinder head bolts, check that the shank length of each bolt meets the limit is exceeded, replace the bolt. Standard value: 120.4 mm (4.740 in.) (2) Apply engine oil to the bolt threads and washers.
Front Case And Oil Pan Removal and Installation 6EN1898 N M A L K B J C I G424 Service Manual Removal steps 1. Oil filter 2. Oil pressure switch 3. Drain plug 4. Drain plug gasket 5. Oil pan 6. Oil screen 7. Oil screen gasket 8. Plug 9. O-ring 10. Flange bolt 11. Relief plug 12. Gasket 13. Relief spring 14. Relief plunger 15. Oil filter bracket 16. Oil filter bracket gasket H G G G F E D D E E 145 C B A 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30.
Removal Service Points MD998727 A Oil pan removal (1) Remove the all oil pan bolts. (2) Drive in the special tool between the cylinder block and oil pan (3) Side the tool by striking the edge of the special tool to separate the oil pan from the cylinder block. 6EN0698 B MD998162 Plug removal (1) Fit special tool MD998162 on the plug, then hold it in position with special tool MD998783. (2) Loose the plug.
D Counterbalance shaft front bearing removal (1) Using the special tool, remove the counterbalance shaft front bearing from the cylinder block. NOTE: Be sure to remove the front bearing first. If it has not been removed, the rear bearing puller cannot be used. MD998371 Front bearing 3EN0166 E Counterbalance shaft rear bearing removal MB991603 (1) Using the special tool, remove the counterbalance shaft rear bearing from the cylinder block.
4. Oil Pump 6LU0013 (1) Assemble the oil pump to the front case and rotate it to ensure smooth rotation with no looseness. (2) Check the side clearance using a thickness gauge. (3) Check the side clearance Standard value: 0.08 to 0.14 mm (0.0031 to 0.0055 in.) Drive gear 0.06 to 0.12 mm (0.0024 to 0.0047 in.) Driven gear Installation Service Points A Right counterbalance shaft rear bearing installation (1) Apply engine oil to the outer surface of bearing.
B MB991603 Left counterbalance shaft rear bearing installation (1) Install the special tool (Guide Plate) to cylinder block. (2) Apply engine oil to the rear bearing outer circumference and bearing hole in the cylinder block. (3) Using the special tool, install the rear bearing. NOTE: The left rear bearing has no oil holes. MD998705 6EN0208 Rear bearing MB991603 MD998705 6EN0557 C Counterbalance shaft front bearing installation (1) Using the special tool, install the rear bearing.
D Socket wrench Oil seal Counterbalance shaft oil seal installation (1) Using a suitable socket wrench, install the counterbalance shaft oil into the front case. Front case 6EN0580 E Oil pump oil seal installation (1) Using a suitable socket wrench, install the oil pump oil seal into the front case. Socket Oil seal Front case 6EN0494 F MD998375 Crank shaft front oil seal installation (1) Using the special tool, install the crankshaft front oil seal into the front case.
H Front case installation (1) Set the special tool on the front end of the crankshaft and apply a thin coat of engine oil to the outer circumference of the special tool to install the front case. MD998285 6EN0746 (2) Install the front case assembly through a new front case gasket and temporarily tighten the flange bolts(other than those for tightening the filter bracket).
J MD998162 Plug installation (1) Install a new o-ring to the groove of the front case. (2) Install a plug to the front case. (3) Fit the special tool MD998162 on the plug, and then hold in position with special tool MD998783. (4) Tighten the plug to the special tool MD998783. (5) Remove the special tools MD998783 and MD998162. MD998783 6EN0909 K FIPG Oil pan installation (1) Clean both mating surface of the oil pan and cylinder block. (2) Apply a 4 mm (0.16 in.
M Oil pressure switch installation Specified sealant: 3MTM AAD Part No. 8672 or equivalent Sealant Caution: 1) Keep the end of threaded portion clear of sealant. 2) Avoid an over tightening. 9EN0094 N Bracket side Engine Oil Oil filter installation (1) Clean the installation surfaces of the filter bracket. (2) Apply engine oil to the o-ring of oil filter. (3) Screw the oil filter in until the o-ring contacts the bracket.
Piston And Connecting Rod Removal and Installation 6EN1899 A G F E D E C G424 Service Manual Removal steps 1. Nut 2. Connecting rod cap 3. Connecting rod bearing 4. Piston and connecting rod assembly 5. Connecting rod bearing 6. Piston ring No. 1 154 B C B A 7. Piston ring No. 2 8. Oil ring 9. Piston pin 10. Piston 11. Connecting rod 12.
Removal Service Points A Cylinder number Connecting rod cap removal Mark the cylinder number on the side of the connecting rod big end for correct reassembly. DEN0050 unit:mm(in) Push rod Guide B Guide C Base Guide A 17.9(0.705) B Piston pin removal The special tool, Piston Pin Setting Tool (MD998780), consists of the parts shown in the illustration at the left. Guide A 18.9(0.744) Guide A 20.9(0.823) Guide A 21.9(0.
Inspection 1. Piston Ring 7EN0475 Press down ring with piston Piston ring End gap (1) Check for the clearance between the piston ring and ring groove. If the limit is exceeded, replace the ring or both piston and ring. (2) Install the piston ring into the cylinder bore. Force it down with a piston, its crown being in contact with the ring, to correctly position it at right angles to the cylinder wall. Then, measure the end gap with a feeler gauge. If the ring gap is excessive, replace the piston ring.
Piston Installation Service Points A Connecting rod Piston pin A7EN0432 Piston pin installation (1) Measure the following dimensions of the piston, piston pin and connecting rod. A: Piston pin insertion hole length B: Distance between piston bosses C: Piston pin length D: Connecting rod (2) Obtain dimension L (to be used later) from the above measurements by using by following formula.
B Side rail Oil ring installation (1) Fit the oil ring spacer into the piston ring groove. First, install the upper side rail, and then install the lower side rail. Spacer 6EN0585 NOTE: 1) The side rails and spacer may be installed in either direction. 2) The new spacers and side rails are painted in the following colors to identify their sizes. Size Identification color STD No color 0.50 mm (0.020 in.) O.S. Blue 1.00 mm (0.040 in.) O.S.
(2) Using piston ring expander, fit No.2 and then No.1 piston ring into position. NOTE: Install piston ring with identification mark facing up, to the piston crown (3) Install the No.1 piston ring in the same manner as step 2. 7EN0452 D Upper side rail No.1 Piston pin No.2 ring gap and space gap Lower side ral 6EN0549 Piston and connecting rod installation (1) Liberally coat engine oil on the circumference of the piston, piston ring, and oil ring.
E No.1 No.4 Connecting rod bearing installation When the bearings are replaced, select and install them according to the identification colors on the crankshaft and identification marks stamped on the connecting rod bearing. Crankshaft Pin No.2 No.3 6EN0700 Pin O.D. Identification Thickness, identification mm (in.) mark or color mm (in.) color Yellow 44.995 to 45.000 (1.77145 to 1.77165) 1 or Yellow None 44.985 to 44.995 (1.77106 to 1.77145) 2 or None White 44.980 to 44.985 (1.77086 to 1.
G Connecting rod cap nut installation (1) Since the connecting rod bolts and nuts are torque using a plastic area tightening method, they should be examined BEFORE reuse. If the bolt threads are “necked down”, the bolts should be replaced. Necking can be checked by running a nut with fingers to the full length of the bolt’s thread. If the nut does not run down smoothly, the bolt should replaced. (2) Before installing the nuts, the threads should be oiled with engine oil.
Crankshaft And Cylinder Block Removal and Installation 6EN1900 F E D C G424 Service Manual Removal steps 1. Flywheel bolt 2. Flywheel 3. F/W Housing 4. Cover - F/W Housing 5. Oil seal case 6. Oil seal 7. Crankshaft bearing cap bolt C B B B 162 8. Crankshaft bearing cap 9. Crankshaft bearing lower 10. Crankshaft 11. Crankshaft bearing upper 12. Thrust bearing 13.
Inspection Plastic gauge 1. Crankshaft Oil Clearance (Plastic Gauge Method) Use of the plastic gauge can facilitate the oil clearance measurement work. To use the plastic gauge, proceed as follows: (1) Remove oil from the crankshaft journal and crankshaft bearing. 6EN0703 (2) Install the crankshaft. (3) Cut the plastic gauge to the same length as the width of the bearing and place it on the journal in parallel with its axis.
3. Cylinder Boring Thrust direction Piston O.D 6En0554 (1) Oversize pistons to be used should be determined on the basis of largest bore cylinder. (2) Oversize pistons are available in four size 0.50 mm (0.0197 in.), and 1.00 mm (0.0394 in.). Rebore the cylinder to a diameter that matches the selected piston outside diameter that matches the selected piston outside diameter with the specified clearance. The reference piston outside diameter measuring point is shown in the illustration.
B Crankshaft bearing installation (1) From the following table, select a bearing whose size is appropriate for the crankshaft journal outside diameter. Crankshaft journal outside diameter Cylinder Crankshaft block bearing bearing for No.3 bore Identification mark or color Identification Size Identification Identification Identification color mm (in.) mark Yellow 56.994 to 57.000 (2.2439 to 2.2241) None White 56.988 to 56.994 (2.2436 to 2.2439) 56.982 to 56.988 (2.2434 to 2.
Crankshaft journal Identification color Cylinder block bearing support section O.D. mm (in.) Yellow Crankshaft bearing Identification mark I.D. mm (in.) Identification mark Thickness mm(in.) 0 61.000 to 61.006 1 1.988 to 1.991 (2.40157 to 2.40181) 56.994 to 57.000 1 (2.24385 to 2.24409) 61.006 to 61.012 (0.07827 to 0.07839) 2 (2.40181 to 2.40204) 2 61.012 to 61.018 (0.07839 to 0.07850) 3 (2.40204 to 2.40228) None 0 61.000 to 61.006 1 (2.24362 to 2.24189) 61.006 to 61.012 2 61.
C 8 4 1 7 3 2 5 6 9 10 6EN0624 Bearing cap/bearing cap bolt installation (1) Install the bearing caps so that their arrows are positioned on the timing belt side. (2) When installing the bearing cap bolts, check that the shank length of each bolt meets the limit. If the limit is exceeded, replace the bolt. Limit: Max. 71.1 mm (2.799 in.) (3) Torque the bearing cap bolts to 2.5 kgf•m (18.1 lb•ft)[25 N•m] and, from that position, retighten them 1/4 (90°) turns more.
E Sealant application to oil seal case. Specified sealant: Silicone RTV sealant or equivalent. Seal ant NOTE: 1) Be sure to install the case quickly while the sealant is wet(within 15 minutes). 2) After installation, keep the sealant area away front the oil and coolant for approx. one hour. 6EN0626 F Rear plate installation (1) Be sure install the spring washers and special washers in correct position.
ADJUSTING AND TROUBLESHOOTING Adjustment The following is the method of adjustment of the carburetor and pneumatic governor on a reassembled engine. Gasoline Rubber cap Caution : (1) The pneumatic governor hss been properly adjusted and sealed in the factory before shipping. Never break the seal unless it is necessary during engine overhaul. (2) If the pneumatic governor is readjusted, seal it again and advise your user that he should not break the seal. Vacuum hose 1.
NOTE Engine timing can be measured at not only engine crankshaft pulley but also flywheel assy. The measurement of engine timing at crankshaft pulley is exact but it is difficult and dangerous. The measurement of engine timing at flywheel side is safe, but it is need to adjust zero position of timing plate like the followings brfore measurement of engine timing. 1) Pull out key from key switch. 2) Remove timing plate(6) from the converter housing. The flywheel shoulder has a single timing mark on it.
(3) While holding the adjust screw to prevent it from turning, rotate the adjusting nut either clockwise or counterclockwise to make the engine run at 2700 L 50 rpm. 3. Idling Speed Adjustment Gasoline Carburetor Adjusting nut: Clockwise rotation Increases the engine speed (increases the installed load of spring). Counterclockwise rotation Decreases the engine speed (decreases the engine installed load of spring). SAS 5.
Troubleshooting Engine Performance Symptom Cause 1. Poor engine idle. A. Clogged air breather. B. Improper idle-fuel mixture adjustment. C. Cap or spark-plug wires arcing. D. Low grade fuel. E. Incorrect ignition timing. F. Spark plugs (fouled, burned, cracked porcelain). G. Spark plug wires broken or faulty insulation. H. Defective coil. I. Cracked or dirty distributor cap. J. Dirty carburetor. K. Leak at intake manifold or carburetor base. L. Low compression. (Check for blown head gasket). M.
Engine Starting Problems (Continued) Symptom Cause 1. No spark. A. Distributor cap or spark plug leads arcing. B. Spark plugs fouled, burned or cracked porcelain. C. Spark plug wires are broken or have faulty insulation. D. Battery, electrical connections, damaged wiring. E. Ignition switch. F. Faulty ignition components. G. Cracked or dirty distributor cap. H. Shorted tachometer. (Disconnect tachometer and try again). 2. Engine will not crank over. A.
Engine Noise No definite rule or test will positively determine the source of engine noise. Therefore, use the following information only as a general guide to engine noise diagnosis. 4. Try to isolate the noise to location in engine, front to back, top to bottom. This can help determine which components are at fault. 5. Sometimes noises can be caused by moving parts coming in contact with other components.
Engine Noise (Continued) Symptom Cause 5. Noise in camshaft area (center of engine). A. Valve lifter. B. Cam bearings. 6. Noise in camshaft area (rear of engine). A. Valve lifter. B. Cam bearings. 7. Noise in crankshaft area (throughout engine). A. Loss of oil pressure. B. Main bearings. C. Rod bearings. 8. Noise in crankshaft area (front of engine). A. Crankshaft timing gear. B. Timing Belt. C. Main bearing. D. Rod bearing. 9. Noise in crankshaft area (center of engine). A.
Oil Pressure Diagnostics The following table contains important information for the checking of oil pressure. Condition Information 1. Measuring oil pressure. Use a good automotive oil pressure test gauge. Do not rely on the oil pressure gauge in the instrument panel. 2. Check engine oil level. Oil level should be between the "MIN" and "MAX" marks. 3. Oil level in crankcase above "MAX" mark.
Oil Pressure Problems Symptom Cause 1. Low oil pressure. A. Low oil level in crankcase. B. Defective oil-pressure gauge and/or sender. C. Oil broken down, contains water, wrong viscosity, engine running too hot or too cold, excessive idling with cold water (condensation). D. Relief valve stuck open, pickup tube restricted, worn parts in oil pump, air leak on suction side of oil pump or pickup tube. E. Oil passage plugs leaking, cracked or porous cylinder block. F. Excessive bearing clearance. 2.
Water in Engine Determine location of water in engine. This information is necessary to determine where the water came from and how it got into the engine. The most common problems are water on top of pistons and/or water in crankcase oil. 1. After locating the water, remove all the water from the engine by removing all spark plugs and pump cylinders by cranking engine over. Next change oil and filter. Start engine and see if problem can be duplicated. If so, there is more than likely a mechanical problem.
Engine Overheating Symptom Cause 1. Mechanically related. A. Engine rpm below specification for W.O.T. (engine laboring). B. Wrong ignition timing. C. Spark plug wires crossed (wrong firing order). D. Lean fuel mixture. E. Wrong heat range spark plugs. F Exhaust restriction. G. Valve timing off caused by a jumped or improperly installed timing chain and/or gears. H. Blown head gasket(s). I. Insufficient lubrication to moving parts of engine. 2. Cooling system related. A. Loose or broken drive belt. B.
LP Fuel System (Standard and/or Low Emission Version) Problem Will Not Start/FCV Staying On Probable Cause Fuel container empty Liquid valve closed Excess flow valve closed Plugged fuel line Clogged fuel filter Faulty vapor connection between pressure regulator and carburetor Fuel lock malfunction Pressure regulator malfunction Will Not Start/FCV Staying On Carburetor malfunction Air filter plugged No spark Engine Mechanical G424 Service Manual 180 Probable Solution Fill fuel container • Do not
Problem Difficult to Start Probable Cause Fuel container almost empty Excess flow valve closed Clogged fuel filter Plugged fuel line Faulty vapor connection between pressure regulator and carburetor Pressure regulator malfunction Air filter clogged Engine Mechanical G424 Service Manual 181 Probable Solution LPG vapor from liquid outlet • Fill fuel container • Do not exceed 80% of liquid capacity Reset excess flow valve • Close liquid valve • Wait for click sound • Open valve slowly Repair/replace
Problem Won’t Run Continuously Probable Cause Fuel container almost empty Excess flow valve closed Clogged fuel filter Plugged fuel line Faulty vapor connection between pressure regulator and carburetor Pressure regulator freezes Incorrect idle speed Engine Mechanical Won’t Accelerate/Hesitation During Acceleration Fuel container almost empty Excess flow valve closed Clogged fuel filter G424 Service Manual 182 Probable Solution LPG vapor from liquid outlet • Fill fuel container • Do not exceed
Problem Won’t Run Continuously Accelerate/Hesitation During Acceleration Probable Cause Faulty vapor connection between pressure regulator and carburetor Probable Solution Check connection • No holes in hose • Clamps must be tight • Watch for kinked and/or pinched and/or collapsed hose Throttle butterfly not opening Verify wide open throttle Incorrect full load air/fuel duty Verify full load air/fuel duty cycle cycle Engine Mechanical See Troubleshooting section Engine Stalls Idle duty cycle too high (a
Problem Engine Stalls Probable Cause Pressure regulator malfunction Pressure regulator freezes Faulty vapor connection between pressure regulator and carburetor Carburetor malfunction Engine Mechanical Rough Idle/Weak Ignition/Lean Condition Incorrect idle speed setting Incorrect full load air/fuel duty cycle Faulty vapor connection between pressure regulator and carburetor Vacuum leaks High Idle Speed Engine mechanical Incorrect idle speed setting Sticking throttle Engine mechanical G424 Service
Problem Carburetor Backfire Probable Cause Incorrect full load air/fuel duty cycle Faulty vapor connection between pressure regulator and carburetor Ignition malfunction Incorrect ignition timing setting Clogged fuel filter Plugged fuel line Faulty vapor connection between pressure regulator and carburetor Throttle butterfly not opening Incorrect full load air/fuel duty cycle Carburetor malfunction Pressure regulator malfunction Incorrect ignition timing setting Air filter clogged G424 Service Manu
Problem Poor High Speed Performance/Lean Condition Probable Cause Restricted exhaust system Engine mechanical Excessive Fuel Consumption/LPG Exhaust Smell/Closed Loop System Not Working Carburetor malfunction Incorrect ignition timing setting Incorrect full load air/fuel duty cycle Engine mechanical Pressure regulator malfunction Check carburetor • Remove air/gas valve assembly • Clean air/gas valve and carb throat • Check diaphragm for holes/damage • Check air/gas valve for wear/damage • Repair/replac
Troubleshooting Flow Chart General Abnormal combustion Loose connection in ignition system wiring –Check connections and retighten. Defective spark plug –Replace spark plug. Incorrect ignition timing –Adjust ignition timing. Defective carburetor –Repair or replace carburetor. Contaminated or clogged fuel filter element and pipe –Clean fuel filter element and pipe. Entry of air from carburetor or intake manifold –Retighten set bolts or replace heat insulator and/or intake manifold gasket.
Insufficient output Poor acceleration Excessive fuel consumption Excessive engine oil consumption Loose fan belt tension –Adjust or replace. Worm or damaged fan belt –Replace. Oil on fan belt –Clean. Thermostat not functioning properly –Replace. Water pump not functioning properly –Replace. Clogged radiator –Clean radiator and coolant passages. Incorrect ignition timing –Adjust ignition timing. Improper engine oil –Refer to lubrication table and replace oil with a recommended one.
Base Engine Valves and related components Poor idling Abnormal combustion Insufficient output Excessive fuel consumption Engine Poor startability Poor acceleration Excessive fuel consumption Insufficient output Incorrect valve clearance –Cleaned or replace auto-lash adjuster. Valve not in close contact with valve seat –Reface seat surface. Excessive clearance between valve stem and valve guide –Replace valve and valve guide. Incorrect valve clearance –Cleaned or replace auto-lash adjuster.
Oil working its way up Engine Excessive oil consumption Piston ring gaps in improper positions –Adjust ring gap positions. Piston rings or ring grooves worn or rings –Replace piston or rings. seized in grooves Carbon deposit in oil return hole of oil ring –Replace rings. Worn piston and cylinder –Rebore and hone cylinder and install oversize piston. Excessive quantity of oil in oil pan –Oil quantity: 4.0 liter (1.1 U.S. gal).
Carburetor Poor engine startability Poor idle Carburetor Abnormal combustion Poor acceleration Insufficient output Excessive fuel consumption G424 Service Manual Needle valve and valve seat not seating properly –Clean or replace Incorrect float level –Adjust Worn float lip –Replace Worn float level pin and related components –Replace level pin and its related parts Malfunction choke valve –Repair Idle rpm set out of adjustment –Adjust idling speed Damaged idle adjust screw –Replace adju
Electrical components Distributor Poor engine starting Cracked distributor cap and burnt or contaminated cord insertion hole –Clean or replace. Poor engine acceleration Centrifugal and vacuum advance device malfunction –Repair or replace. Improper spark plug gap –Adjust or replace. Carbon deposit in spark plug –Clean or replace. Improper heat range of spark plug –Replace spark plug with proper one. Loose or defective plug cord –Repair or replace.
Starter Starter does not rotate. Starter rotates but slowly and irregularly. Pinion does not engage with ring gear. Motor continues to rotate and does not stop. G424 Service Manual Brush holder not properly insulated –Clean brush or replace holder. Worn bearing bushing –Replace bushing. Wires of armature coil about to be shortcircuited or grounded –Rewind or replace. Field coil not properly connected or about to be short-circuited –Repair connections.
Battery Run-down battery Drive belt slipping –Adjust belt. Alternator Stator coil grounded or open-circuited –Replace or repair. Rotor coil open-circuited –Replace. Brush and slip ring not properly connected (Brush does not properly come down) –Replace brush if worn. (Clean holder.) –Polish slip ring. Diode short-or open-circuited –Replace rectifier assembly. Battery Short or improper electrolyte –Add electrolyte and adjust specific gravity. Defective plates (internal short circuit) –Replace.
SPECIAL TOOLS Style G424 Service Manual Tool No.
Style G424 Service Manual Tool No.
Style G424 Service Manual Tool No.
ITK-1 Pressure Gauge Kit FSA-1000 Fuel System Analyzer The IMPCO ITK-1 pressure gauge kit is designed for testing and troubleshooting IMPCO gaseous fuel systems. The kit contains the following: See instructions for proper usage to check air/fuel mixture. ● 0-160 psi gauge - For measuring fuel container pressure or on dual fuel systems it may be used to measure gasoline fuel system pressure. ● 0-5 psi gauge - For measuring IMPCO pressure regulator, primary pressure.
