SD-01-336 ® Bendix® TU-FLO® 600 Air Compressor TU-FLO® 600 AIR COMPRESSOR VERTICAL MOUNT GENERAL The function of the air compressor is to build up and maintain the air pressure required to operate air powered devices in air brake or air auxiliary systems. DESCRIPTION The Tu-Flo® 600 compressor is a two cylinder reciprocating single stage compressor with a rated displacement of 14.5 cfm at 1250 rpm. The Tu-Flo® 600 compressor is constructed with a crankcase, block, and head assembly.
FIGURE 2 - TU-FLO® 600 AIR COMPRESSOR SECTIONAL VIEW NEW DESIGN OLD DESIGN WRIST PIN BUSHING WRIST PIN OIL PASSAGE WRIST PIN BUSHING PISTON WRIST PIN LOCK WIRE CAST IRON PISTON STEEL CONNECTING ROD “CATCH FUNNEL” TEFLON PLUG DIE CAST PISTON DIE CAST CONNECTING ROD FIGURE 3 - TU-FLO® 600 AIR COMPRESSOR PISTON/PIN DESIGN NAME PLATE FIGURE 1 - FLANGE CONFIGURATIONS 2 A name plate is attached to the crankcase of all compressors. It shows the piece number, type and serial number (Fig. 4).
TO RESERVOIR INLET VALVE UNLOADER PLUNGER DISCHARGE VALVE INTAKE STRAINER PISTON FIGURE 4 OPERATION TO GOVERNOR GENERAL STROKE All compressors run continuously while the engine is running, but actual compression of air is controlled by a governor which stops or starts the compression of air by loading or unloading the compressor in conjunction with its unloading mechanism. This is done when the air pressure in the system reaches the desired maximum or minimum pressures.
The Air Brake Charging System supplies the Discharge Line Optional “Ping” Tank Air Dryer compressed air for the braking system as well as other air accessories for the vehicle. The system usually consists of an air compressor, governor, discharge line, air dryer, and service reservoir.
HOLE THREAD FIGURE 8B - DISCHARGE LINE SAFETY VALVE FIGURE 9 - SPONGE TYPE STRAINER DISCHARGE LINE TEMPERATURE DRY ELEMENT - PLEATED PAPER AIR STRAINER (FIG. 10) When the temperature of the compressed air that enters the air dryer is within the normal range, the air dryer can remove most of the charging system oil. If the temperature of the compressed air is above the normal range, oil as oilvapor is able to pass through the air dryer and into the air system.
Always use a new mounting gasket and be sure oil hole in gasket and compressor is properly aligned with oil supply line. Inspect pulley or gear and associated parts for wear or damage. They must be a neat fit on compressor crankshaft. Replace pulley or gear if worn or damaged. FIGURE 11 - INLET ADAPTER AIR LEAKAGE TESTS Leakage past the discharge valves can be detected by removing the discharge line, applying shop air back through the discharge port and listening for escaping air.
The discharge valve cap nuts should be inspected for wear and replaced if excessive peening has occurred. To determine if excessive peening has occurred, measure the discharge valve travel. Discharge valve travel must not exceed .046 inches (1.168 mm). If the pistons are removed from the rod, inspect the bronze wrist pin bushing. Press out and replace the bushing if it is excessively worn. (See inspection of parts.) Discard the piston rings and the connecting rod journal bearings.
FIGURE 13 - TU-FLO® 600 AIR COMPRESSOR CYLINDER BLOCK ASSEMBLY FIGURE 14 - TU-FLO® 600 AIR COMPRESSOR CRANK CASE ASSEMBLY 8
CYLINDER HEAD ASSEMBLY Remove all carbon deposits from discharge cavities and all rust and scale from cooling cavities of cylinder head body. Scrape all foreign matter from body surfaces and use air pressure to blow dirt particles from all cavities. Discharge valves can be dressed by lapping them on a piece of fine crocus cloth on a flat surface, provided they are not excessively worn. CYLINDER BLOCK Clean carbon and dirt from inlet and unloader passages.
CYLINDER BLOCK Check for cracks or broken lugs on cylinder block. Also check unloader bore bushings to be sure they are not worn, rusted or damaged. If these bushings are to be replaced, they can be removed by running a 1/8 in. pipe thread tap inside the bushing, then inserting a 1/8 in. pipe threaded rod and pulling the bushing straight up and out. Do not use an easy-out for removing these bushings.
TU-FLO® 500 & 600 AIR COMPRESSOR INCHES CORRECT GROOVE CLEARANCE NARROW WIDE RING RING NARROW .0015 REPAIRS MM .038 WIDE .0035” .0015” .002” .004” CORRECT GAP CLEARANCE WITH RING IN CYLINDER .0035 .015 NARROW WIDE .002 .051 .0035 .089 .004 .102 .015 .381 FIGURE 18 - PISTON RING POSITIONS GAPS & GROOVE CLEARANCE CRANKSHAFT Check crankshaft screw threads, keyways, tapered ends and all machined and ground surfaces for wear, scores, or damage.
Position a rear end cover gasket, when used, over the rear end of the crankcase, making sure the oil hole in the gasket lines up with the oil hole in the crankcase. Position the end cover oil seal ring, if used, in the groove in the end cover boss. The end cover should be positioned correctly in relation to the oil holes in the gasket and crankcase. As the end cover is positioned, the oil seal ring must be compressed as it is positioned in the crankshaft.
FIGURE 19 - SPONGE TYPE AIR STRAINER EXPLODED VIEW A compressor efficiency or build-up test can be run which is not too difficult. An engine lubricated compressor must be connected to an oil supply line of at least 15 pounds pressure during the test and an oil return line must be installed to keep the crankcase drained. The compressor (when tested) should be tested without a strainer.
5. Following the vehicle manufacturer’s recommended procedures, deactivate the electrical system in a manner that safely removes all electrical power from the vehicle. 6. Never exceed manufacturer’s recommended pressures. 7. Never connect or disconnect a hose or line containing pressure; it may whip. Never remove a component or plug unless you are certain all system pressure has been depleted. 8. Use only genuine Bendix® replacement parts, components and kits.
This troubleshooting guide obsoletes and supersedes all previous published troubleshooting information relative to Bendix air compressors. Advanced Troubleshooting Guide for Air Brake Compressors * The guide consists of an introduction to air brake charging system components, a table showing recommended vehicle maintenance schedules, and a troubleshooting symptom and remedy section with tests to diagnose most charging system problems.
Introduction to the Air Brake Charging System Powered by the vehicle engine, the air compressor builds the air pressure for the air brake system. The air compressor is typically cooled by the engine coolant system and lubricated by the engine oil supply.
Table A: Maintenance Schedule and Usage Guidelines Regularly scheduled maintenance is the single most important factor in maintaining the air brake charging system. Vehicle Used for: No. of Axles Column 1 Column 2 Typical Compressors Spec'd Discharge Line I.D. Length 1/2 in. 6 ft. Column 3 Recommended Air Dryer Cartridge Replacement1 Column 4 Recommended Reservoir Drain Schedule2 Column 5 Acceptable Reservoir Oil Contents3 at Regular Drain Interval e.g.
Air Brake Charging System Troubleshooting How to use this guide: Find the symptom(s) that you see, then move to the right to find the possible causes (“What it may indicate”) and remedies (“What you should do”). Review the warranty policy before performing any intrusive compressor maintenance. Unloader or cylinder head gasket replacement and resealing of the bottom cover plate are usually permitted under warranty. Follow all standard safety procedures when performing any maintenance.
Symptom: What it may indicate: What you should do: 2.0 Oil on the Outside of the Compressor Engine and/or other accessories leaking onto compressor. Find the source and repair. Return the vehicle to service. 2.1 Oil leaking at compressor / engine connections: (a)Leak at the front or rear (fuel pump, etc.) mounting flange. ð Repair or replace as necessary. If the mounting bolt torques are low, replace the gasket. (b)Leak at air inlet fitting. ð Replace the fitting gasket.
Symptom: What it may indicate: 4.0 Oil in Supply or Service Reservoir (air dryer installed) What you should do: Maintenance (a) If air brake charging system maintenance has not been (If a maintained Bendix performed.
Symptom: What it may indicate: 4.0 Oil in Supply or Service Reservoir* (air dryer installed) (continued) What you should do: Temperature (e) Air compressor discharge and/or air dryer inlet temperature too high. ð Check temperature as outlined in Test 3 on page 28. If temperatures are normal go to 4.0(h). (f) Insufficient coolant flow. ð Inspect coolant line. Replace as necessary (I.D. is 1/2"). ð Inspect the coolant lines for kinks and restrictions and fittings for restrictions. Replace as necessary.
Symptom: 4.0 Oil in Supply or Service Reservoir* (air dryer installed) (continued) What it may indicate: What you should do: Other (cont.) (i) Poorly filtered inlet air (poor air quality to compressor). Inspect the engine air cleaner. ð Check for leaking, damaged or defective compressor air inlet components (e.g. induction line, fittings, gaskets, filter bodies, etc.). Repair inlet components as needed. Note: Dirt ingestion will damage compressor and is not covered under warranty.
Symptom: What it may indicate: What you should do: 6.0 Excessive oil consumption in engine. A problem with engine or other engine accessory. ð See engine service manual. 7.0 Oil present at air dryer cartridge during maintenance. Air brake charging system is functioning normally. The engine service manual has more information. Oil shown leaking from an air dryer cartridge. ð Air dryers remove water and oil from the air brake charging system. A small amount of oil is normal.
Symptom: 9.0 Air brake charging system seems slow to build pressure. (continued) What it may indicate: What you should do: (f) Restricted discharge line. ð If discharge line is restricted: ð By more than 1/16" carbon build up, replace the discharge line (see Table A, column 2, on page 17 for recommended size) and go to Test 3 on page 28. ð By other restrictions (e.g. kinks). Replace the discharge line. See Table A, column 2, on page 17 for recommended size. Retest for air build.
Symptom: 10.0 Air charging system doesn’t build air. What it may indicate: What you should do: (a) Governor malfunction*. ð Go to Test 4 on page 29. (b) Restricted discharge line. ð See 9.0(f). (c) Air dryer heater malfunction: exhaust port frozen open. ð Replace air dryer heater. (d) Compressor malfunction. ð Replace the compressor only after making certain the preceding conditions do not exist.
Symptom: 12.0 Air dryer safety valve releases air. What it may indicate: What you should do: (a) Restriction between air dryer and reservoir. ð Inspect delivery lines to reservoir for restrictions and repair as needed. (b) Air dryer safety valve malfunction. ð Verify relief pressure is at vehicle or component manufacturer specifications. Replace if defective. (c) Air dryer performed. ð See Maintenance Schedule and Usage Guidelines (Table A, column 3, on page 17).
Symptom: 16.0 Compressor leaks air What it may indicate: (a) Compressor leaks connections or ports. at ð Check for leaking, damaged or defective compressor fittings, gaskets, etc. Repair or replace as necessary. ð Go to Test 6 on page 29. (c) Damaged gasket. head ð An air leak at the head gasket may indicate a downstream restriction such as a freezeup or carbon blockage and/or could indicate a defective or missing safety valve. Find blockage (go to 9.0(f) for details.) and then replace the compressor.
Tests Test 1: Excessive Oil Leakage at the Head Gasket Exterior leaks at the head gasket are not a sign that oil is being passed into the air charging system. Oil weepage at the head gasket does not prevent the compressor from building air. Observe the amount of weepage from the head gasket. If the oil is only around the cylinder head area, it is acceptable (return the vehicle to service), but, if the oil weepage extends down to the nameplate area of the compressor, the gasket can be replaced.
Tests (continued) Test 4: Governor Malfunction 1. Inspect control lines to and from the governor for restrictions (e.g. collapsed or kinked). Repair as necessary. 2. Using a calibrated external gauge in the supply reservoir, service reservoir, or reservoir port of the D-2™ governor, verify cut-in and cutout pressures are within vehicle OEM specification. 3. If the governor is malfunctioning, replace it. Test 5: Governor Control Line 1.
Appendix A: Information about the BASIC Test Kit (Bendix P/N 5013711) Service writer records info - including the number of days since all air tanks were drained - and fills out symptom checklist. Technician inspects items. days Bendix® Air System Inspection Cup (BASIC) Test Information START BASIC TEST Park vehicle on LEVEL ground. Chock wheels, drain air from system. Drain contents of ALL air tanks into BASIC cup Is there less than one unit of liquid? Vehicle OK. Return vehicle to service.
Appendix A continued: Information about the BASIC Test Kit (Bendix P/N 5013711) ® Filling in the Checklist for the Bendix Air System Inspection Cup (BASIC) Test Note: Follow all standard safety precautions. For vehicles using a desiccant air dryer.
Appendix A continued: Information about the BASIC Test Kit (Bendix P/N 5013711) ® Filling in the Checklist for the Bendix Air System Inspection Cup (BASIC) Test Note: Follow all standard safety precautions. For vehicles using a desiccant air dryer. 2. Record amount of oil found: The Technician uses the chart (label) on the BASIC test cup to help decide the action to take, based on the amount of oil found.
Appendix B Technical Bulletin Bulletin No.: TCH-008-021 Subject: Effective Date: 11/1/92 Page: 1 of 2 Air Brake System - Cold Weather Operation Tips As the cold weather approaches, operators and fleets alike begin to look to their vehicles with an eye toward “winterization”, and particularly what can be done to guard against air system freeze-up. Here are some basic “Tips” for operation in the cold weather.
Appendix B: Continued Bulletin No.: TCH-008-021 Effective Date: 11/1/92 Page: 2 of 2 High Duty Cycle Vehicles (City Transit Coaches, Refuse Haulers, Etc.) The maximum discharge line length is 16 feet. Length I.D. min. Other Requirements 10-16 ft. ½ in. None If the discharge line length must be less than 10 feet or greater than 16 feet, contact your local Bendix representative.
Appendix B: Continued Technical Bulletin Bulletin No.: TCH-008-022 Subject: Additional Effective Date: 1/1/1994 Page: 1 of 1 Cold Weather Operation Tips for the Air Brake System Last year we published Bulletin PRO-08-21 which provided some guidelines for “winterizing” a vehicle air brake system. Here are some additional suggestions for making cold weather vehicle operation just a little more bearable.
BW 1560 © 2004 Bendix Commercial Vehicle Systems LLC All rights reserved. 9/2004 Printed in U.S.A.
