Professional Shop Manual 32 cc Back Pack Blower NOTE: These materials are for use by trained technicians who are experienced in the service and repair of outdoor power equipment of the kind described in this publication, and are not intended for use by untrained or inexperienced individuals. These materials are intended to provide supplemental information to assist the trained technician. Untrained or inexperienced individuals should seek the assistance of an experienced and trained professional.
Table of Contents Chapter 1: Introduction ......................................................................................................... 1 Introduction .........................................................................................................................1 Fasteners .............................................................................................................................1 Assembly ................................................................................
INTRODUCTION CHAPTER 1: INTRODUCTION Introduction Fasteners The 32cc backpack blower is a full crank, 4-cycle blower. It was introduced in the 2008 season under a variety of brand names. This blower has 32cc’s of displacement and produces a maximum of 475 cfm at 150 mph. • Most of the fasteners used on the blower are sized in fractional inches. Some are metric. For this reason, wrench sizes are frequently identified in the text, and measurements are given in U.S. and metric scales.
INTRODUCTION The model (item) number and serial number are printed with a small type face, above the bar code. See Figure 1.3. Model and serial numbers The model (item) and serial number for this blower are on a little white sticker with bar code. These are the numbers needed when ordering parts. This sticker can be found at the bottom of the starter housing by. See Figure 1.2. Serial number Model (item) number Model number Sticker Fuel tank Figure 1.
Maintenance CHAPTER 2: MAINTENANCE MAINTENANCE 2. Wear rate will vary somewhat with severity of use. If the edges of the center electrode are rounded-off, or any other apparent wear / damage occurs, replace the spark plug before operating failure (no start) occurs. 3. Cleaning the spark plug: The specifics in this manual are aimed at the 32cc back pack blower, however the contents can be used for most outdoor power equipment.
Maintenance 2. Spark plug removal 1. Disconnect the spark plug wire. See Figure 2.4. Remove the engine cover by: 1a. Remove the screws that hold the cover in place. NOTE: There are eight screws for the engine cover, four that go into the engine block casting and three that go into the blower housing and one into the fuel tank bracket. Make sure you put the machine threaded screws into the casting and the plastic threaded screws into the blower housing and fuel tank bracket. See Figure 2.2.
Maintenance Air filter 8b. Remove the foam air filter. See Figure 2.7. A dirty air filter can reduce engine power, increase fuel consumption and make starting more difficult. Foam air filter The air filter should be cleaned every 10 hours of use. 8. To clean/replace the air filter: 8a. Press down the on tab of the air filter cover and swing the cover up. See Figure 2.6. Figure 2.7 8c. Wash the air filter with warm soapy water. Let the filter air dry. DO NOT wring the filter out.
Maintenance Spark arrestor Fuel filter The spark arrestor should be checked and/or cleaned every 10 hours of use. A dirty fuel filter can result in a lean run condition. The fuel filter should be replaced every 10 hours of use. NOTE: The spark arrestor also serves to keep blockages out of the exhaust system. Typical blockages include insect nests built during the dormant season. NOTE: The weighted fuel filter (clunk) keeps the filter submerged in the fuel at any angle of operation.
Maintenance 4. Carefully remove the fuel line from the barb on the fuel filter. Clean or discard the old fuel filter. See Figure 2.11. Valve lash To adjust the valves: 1. Remove the engine cover and spark plug by following the steps described in the spark plug section of this chapter. 2. Remove the valve cover using a T-25 driver. See Figure 2.12. Valve cover barb Figure 2.11 5. Inspect the fuel lines. Replace if they are cracked. 6.
Maintenance 4. Starter Check the valve lash by placing a feeler gauge between the rocker arm and the valve stem. To adjust the valve loosen or tighten the fulcrum nut with a 8mm wrench until there is a slight drag on the feeler gauge when you pull it out. See Figure 2.13. The starter and engine cover are one piece on this blower. The procedure for removing it are covered in the spark plug section of this manual. The rewind spring underneath the starter pulley is extremely difficult to work with.
Trouble shooting CHAPTER 3: TROUBLE SHOOTING 1c. Get a sample of fuel from the carburetor and pour it on the section of the paper labeled sample from carburetor. See Figure 3.1. Initial Trouble Shooting The first step in diagnosing an engine problem is to perform the periodic maintenance. A majority of the poor run or no start conditions will be solved just by doing the required maintenance. After the periodic maintenance is done: 1. Drain and inspect the fuel from the fuel tank: • Look for water.
Trouble shooting Most gasoline engine diagnosis involves isolating problems in the four critical factors an engine needs to run properly: 1e. Match the sample from the carburetor to the other three samples. This will show if the proper mix is being used or not. See Figure 3.3. Ignition- sufficient spark to start combustion in the cylinder, occurring at the right time. Compression- enough pressure in the cylinder to convert combustion into kinetic motion.
Trouble shooting 5. Testing compression: 3. NOTE: If the engine will run, start the engine and let it warm up first for a better reading. NOTE: The starter is part of the engine cover and therefore can not be used to rotate the engine. A cordless drill can be used to rotate the engine. See Figure 3.5. Compression testing The compression of an engine can be tested in one of two ways; a compression test or a leak down test. IMPORTANT: Never use an impact wrench to rotate the engine.
Trouble shooting 4. To preform a leak down test: Read the gauge. See Figure 3.6. 1. Remove the engine cover and spark plug by following the steps described in the spark plug section of Chapter 2: Maintenance. 2. Rotate the crankshaft until the piston is at top dead center. 3. Thread the tester adapter into the spark plug hole. See Figure 3.7. Figure 3.6 Leak down tester NOTE: If the engine has less than 80 psi (5.
Trouble shooting 5. Connect the tester to an air source set to 90 psi. 6. Adjust the regulator until the needle on the gauge is in the set region of the gauge. See Figure 3.9. 9. Compare the results to the following chart. Symptom The “set” region of the gauge Air escaping from the breather Worn cylinder or piston rings.
Ignition CHAPTER 4: IGNITION 1e. Rapidly rotate the engine while watching the spark tester for sparks. Troubleshooting the Ignition System The purpose of the ignition system is to provide and deliver a spark to ignite the fuel/air charge in the cylinder at the proper time. NOTE: The starter is part of the engine cover and therefore can not be used to rotate the engine. A cordless drill can be used to rotate the engine. See Figure 4.2.
Ignition 2. 3. To test the module: 2a. Remove the blower housing as described in the blower housing chapter of this manual to expose the module. To test the engine stop switch: 3a. Open the grip by removing the eight screws with a T-25 driver. 3b. Disconnect the wires from the engine kill switch. See Figure 4.4. 2b. Check the air gap for the module. Set it to .010 (.25 mm) by following the steps described in the module section of this chapter. 2c. Disconnect both wires. See Figure 4.3.
Ignition 3e. Hold the switch in the stop position (0). The meter should indicate continuity. See Figure 4.6. Module NOTE: To service the Ignition system (excluding the spark plug) the blower housing must first be removed. To remove the blower housing please refer to the chapter on the Blower Housing. Remove the ignition module: Hold the switch in the off position and read the dvom 1. Disconnect the two wires from the module. See Figure 4.7. Remove these two wires Figure 4.
Ignition 5. Flywheel Place a brass or plastic .010” feeler gauge on the flywheel magnets and rotate the flywheel until the magnets line up with the module. Let the magnets draw the module against the flywheel with the feeler gauge trapped between them. See Figure 4.8. To remove the flywheel: 1. Remove the spark plug by following the steps described in Chapter 2: Maintenance. 2. Insert at least 18”(.5 M) of starter rope in the spark plug hole to keep the crank shaft from rotating.
Ignition 6. Inspect the flywheel and key for any signs of damage. 7. Install the flywheel by following the previous procedure in reverse order. NOTE: Tighten the Impeller shaft to a torque of 120 - 140 in lbs (13.5 - 16 Nm). NOTE: Set the module air gap by following the steps described in the previous section of this manual. 8. Test run the engine before returning it to service.
FUEL SYSTEM AND CARBURETOR CHAPTER 5: FUEL SYSTEM AND CARBURETOR 3. Troubleshooting the Fuel System 3a. Are they cracked? The function of the fuel system is to store, mix the fuel with air and deliver it to the engine. The fuel system consists of the following components: • Fuel tank • Fuel lines • Fuel filter • Carburetor 3b. Are they clogged? 3c.
FUEL SYSTEM AND CARBURETOR 3. Repairing the fuel system Remove the fuel tank: Remove the two screws holding the fuel tank bracket to the blower housing. See Figure 5.5. CAUTION: Drain all fuel out of the blower before attempting to work on the fuel system. 1. Disconnect the fuel lines from the carburetor or at the line splices. See Figure 5.3. Remove these screws Line splices Figure 5.5 4. Remove the three screws that hold the tank to the bracket. See Figure 5.6. Figure 5.3 2.
FUEL SYSTEM AND CARBURETOR Fuel lines Troubleshooting/Repairing the Carburetor To remove the fuel lines: Typically, troubleshooting the carburetor is the last step in the diagnostic process. The other factors are more readily identified; spark vs. no spark, specific pressure readings on a compression gauge, or a visible blockage in the muffler. Carburetor function is more subtle.
FUEL SYSTEM AND CARBURETOR 5. 7. Inspect and clean the vent under the primer body for debris. See Figure 5.8. Inspect the throttle valve assemble for debris and freedom of movement. See Figure 5.10. Throttle valve assembly Vent Figure 5.8 6. If the carburetor is running lean: • Inspect the carburetor spacer for cracks. • Inspect the spacer gasket. Figure 5.10 8.
FUEL SYSTEM AND CARBURETOR 7b. Remove the four screws going through the primer bulb housing with a #0 phillips screwdriver. 7f. 7c. Separate the carburetor, placing each part on the bench in the order they came apart. NOTE: If there is a minor amount of dirt/varnish in the carburetor it would be worth while to clean and rebuild the carburetor by following the procedures recommended by the carburetor manufacturer. 7d. Inspect the metering valve and the metering valve seat for dirt and/or pitting.
FUEL SYSTEM AND CARBURETOR 7m. There are ports in the metering valve body. it is important to make sure they are clean and free of debris. 7j. The fuel pump in the carburetor is driven by vacuum pulses in the intake port. The impulse port from the spacer lets the vacuum pulses into the pump chamber. See Figure 5.14. 7n. Follow steps in reverse order to rebuild the carburetor. Impulse port Figure 5.14 7k. Make sure this port is clean and free of debris. 7l.
Blower housing CHAPTER 6: BLOWER HOUSING 4. Back pack frame 1. Remove the grip housings from the blower tube. NOTE: Put the two grip housings back together and secure with a couple of screws to keep the switch, trigger, wires and cable in place while working on the blower. Remove the four nuts that hold the back pack frame to the shock mounts. See Figure 6.1. 5. Slide back pack off of the blower. NOTE: If the throttle cable is wire tied to the back pack mount, cut the wire tie.
Blower housing 4. Blower housing and impeller 1. Lift the impeller off of the flywheel. NOTE: Inspect the impeller for any signs of cracks or damage. Replace if any is found. A damaged or cracked impeller will turn into shrapnel when the blower is running. Remove the nine screws that hold the blower housing together with a T-25 torx driver. See Figure 6.3. 5. Remove the lower blower housing by removing the four screws with a T-25 torx driver. See Figure 6.5.
