V-ENGINE SERVICE MANUAL Table of Contents – Page 1 of 3 ABOUT THIS MANUAL SAFETY INFORMATION SPECIFICATIONS ENGINE SPECIFICATIONS ENGINE FASTENER TORQUE REQUIREMENTS CARBURETOR SPECIFICATIONS SPECIAL TOOL REQUIREMENTS SPECIAL TOOL REQUIREMENTS - REQUIRED SERVICE SUPPLIES TORO 2-CYCLE V ENGINE TOOL REQUIREMENTS TROUBLESHOOTING ENGINE WILL NOT START WHEN "COLD" ENGINE WILL START WHEN "COLD", BUT NOT WHEN "HOT" ENGINE WILL NOT PRODUCE SPARK ENGINE FLOODED WITH FUEL ENGINE HAS LOW COMPRESSION ENGINE LACKS POWER
V-ENGINE SERVICE MANUAL Table of Contents – Page 2 of 3 PRIMER START CARBURETOR - Continued OPERATION GOVERNOR GOVERNOR ADJUSTMENT SERVICING - PRELIMINARY CHECK DISASSEMBLY CLEANING AND INSPECTION ASSEMBLY INSTALLATION PRESETTING THE GOVERNOR SERVICING THE AIR FILTER FUEL SYSTEM OPERATION - FUEL TANK FUEL CAP SERVICE - FUEL CAP TANK REMOVAL CLEANING TANK INSTALLATION FUEL STORAGE IGNITION SYSTEM TROUBLESHOOTING - PROCESS SPARK PLUG - OPERATION SERVICE CD PACK - ADVANTAGES OPERATION AIR GAP ADJUSTMENT REMOVA
V-ENGINE SERVICE MANUAL Table of Contents – Page 3 of 3 ENGINE - Continued MUFFLER PLATE SCREWS EXHAUST PORTS CARBURETOR GASKETS REMOVAL DISASSEMBLY INSPECTION AND REPAIR REED VALVE SERVICE REASSEMBLY REINSTALLING EXTERNAL COMPONENTS PIVOTING ZONE START BRAKE SYSTEM PIVOTING ZONE START BRAKE - INTRODUCTION OPERATION DISASSEMBLY ASSEMBLY APPENDIX POWER HEAD - EXPLODED VIEW IGNITION AND EXHAUST - EXPLODED VIEW STARTER AND PRIMER START CARBURETOR - EXPLODED VIEW PRIMER START CARBURETOR ASSEMBLY - EXPLODED VIEW
ABOUT THIS MANUAL ThismanualwaswrittenexpresslyfortheTor0 V Engine.TheTor0Companyhas made every effortto make the informationin this manual complete and correct. This manual was written with the service' technician in mind. The book is divided into two sections, Quick Reference information (specifications, troubleshooting, etc.) and servicing information (servicing procedures). We hope you find this manual a valuable addition to your service shop.
Safety Information This safety symbol means WARNING or PERSONAL SAFETY it has to do with your INSTRUCTION - read the instruction because safety. Failure to comply with the instruction may resultin personal injury or even death. This manual is intended as a service and repair manual only. The safety instructions provided herein are for troubleshooting, service and repair of the engine only. The Operator’s Manual will contain safety information onthe complete product powered by theTor0 2-Cycle V engine.
QUICK REFERENCE SECTION Specifications .............................................. ................................... Special Troubleshooting ............................................ Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SERVICE SECTION Primer Start Carburetor.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Fuelsystem ............................................... IgnitionSystem ................
Engine Specifications.
Engine Specifications I I Section Reference 1-3
Bolt, Blade 81.6N-m) Nut, Flywheel Screw, Air vane Screw, Carburetor mounting Screw, CD ignition pack Screw, Cylinder to crankcase Screws, Engine mounting Screw,Groundstrapstop Screw, Muffler cover Screw, Muffler plate ~- 90 110 in lbs(10-12N-m) 105 I 115inlbs (.I2I 3 N-m 350-400in Ibs (39 45 N-m) 15 25 in Ibs (1.7 2.8N-m) 150 190 in Ibs (I7 22 Nom)-. 140 200 in Ibs (16 22 N-m) Screw, Reed* 10 1 3Ibs(1.1-1.5 in Screw, Shroud 65 75 in Ibs (7,3- 8 . 4 N-m) 20 25 in Ibs (2.3 2.
QUICK REFERENCE SECTION Specifications 2 Special Tool Requirements. Troubleshooting Maintenance SERVICE SECTION Primer Start Carburetor. Fuelsystem Ignition System Rewind Starter. Engine Pivoting Zone StartBrake.
CE REQUIRED 2-2 Reference Section
QUICKREFERENCESECTION Specifications Special Tool Requirements. 3 Troubleshooting Maintenance SERVICE SECTION Primer Start Carburetor. Fuelsystem Ignition System Rewind Starter. Engine Pivoting Zone StartBrake.
COLD” WHEN STARTNOT WILL ENGINE 3-2 3-3 ENGINE WILL START WHEN “COLD”, BUT NOT WHEN “HOT” 3-3 ENGINE WILL NOT PRODUCESPARK. 3-3 ENGINE BACKFIRES 3-5 ENGINE OVERHEATS. 3-5 ENGINE VIBRATES EXCESSIVELY. 3-5 ENGINE CRANKSHAFTWILL NOT TURN.. 3-5 SPARK PLUG FOULED.
“COLD” WHEN START NOT WILL ENGINE Remedies Fill with clean,fresh, properly mixed, unleaded fuel Drain and flush tank and float bowl, fill tank with clean fresh unleaded, properly mixed fuel Clean and backflush fuel tank.
ENGINE FLOODED WITH FUEL Remedies Let unit sit, retry, or, remove spark plug, pull rope several times.. Reinstall plug. Try again.
Section Reference 3-5
ENGINE PRODUCES MECHANICAL KNOCKING SOUND Remedies Inspect and tighten bladebolt tocorrect torque Inspect and tighten flwheel nut to correct torque S e e “ENG!NEPRE-IGNITES’table I n s p e c t and repair and tighten-nuts to correct torque bolts Tighten ENGINE SMOKES EXCESSIVELY ENGINE STALLS Remedies Refill with fresh fuel-of the correct mixture Unload engine and-restart See “SPARK PLUG FOULEDtable Replace fuel cap Inspect and repairto removeunwanted ground Clear ventof obstruction Clear debris from fin
SPARK PLUG FOULED possible Causes ~Incorrect spark plug Carburetor running too rich Clogged air cleaner element Weakignition syslem Worn rings and/or cylinder Use of leaded fuel Fuel/oil mixture too rich Wrong oil Section Usecorrectsparkplug Clean-!rebuild carburetor Clean and re-oil or replace element Replace CD ignition pack Rebuild engine orshort block Drain fuel tank and replace with fresh, unleaded regular fuel, having the correct oil mixture Drain fuel tank andfill with fuel of correct mixture (32:1
QUICK REFERENCE SECTION Specifications Special Tool Requirements. Troubleshooting e Maintenance SERVICE SECTION Primer Start Carburetor. Fuelsystem Ignition System Rewind Starter. Engine Pivoting Zone StartBrake.
4-2 AIR FILTER Cleaning 4-3 4-3 Spark Plug Spark Plug Gap Spark Plug Torque 4-4 4-5 4-5 Exhaustsystem Cleaning Reassembling 4-5 4-5 4-7 Reference Section
RECOMMENDED MAINTENANCE SCHEDULE item Comments Fasteners 25 Hours 50 Hours 100 Hours Check blade and engine mounting fasteners frequently. all Keep nuts, tightbolts Air filter Remove,and clean each mowing season or every 25 hours: more frequently if operating conditions-aredusty.
AIR FILTER (cont'd Cleaning (cont'd) 2. Wash the air filter in dish or laundry detergent. Squeeze the filterto remove excess liquid and blot dry with a clean paper towelor rag. NOTE: Do not wring out the elementor damage may occur. 751.2.5130.801 3. Apply one tablespoon of SAE 1OW30, or similar, oil to the air filter. Lightly squeeze the filter until the is oildistributed evenly throughout the filter. Blot lightly with a clean paper towel or rag to remove excess oil.
Gap Plug Spark Set the spark plug gapto .035"(.85mm). Spark Plug Torque Install thespark plug finger tight, then torque to 180 in Ibs (15ft. Ibs.) (20 Nm),or 1/4 turn after plug and gasket are seated. 751.1 0490 A4 Exhaust System Cleaning WARNING: Disconnect the spark plug wire to prevent accidentally starting the engine. TOOLS REQUIRED: 1/2" drive 5/8" socket 3/8"(9mm) wooden dowel 1. Wearing heavy duty gloves hold the blade while removing the bolt.
Exhaust System (cont'd) Cleaning (cont'd) 2. The small louvers in the muffler cover must be open and free of debris. Clean if necessary. 3. To remove the muffler cover, remove the three bolts. Drop the cover down to inspect the conditionof the exhaust ports, etc. 751.1.0490.79 4. Pull the starter rope until the piston covers the exhaust ports, this prevents carbon from falling into the cylinder. Clean exhaust 3/8"(9mm) wooden port area with the dowel.
Reassembling Insert the three bolts into the muffler cover 1. and torque to 150-1 90 in Ibs (17-22 Nm). 2. Check the condition of the key and keyway. If OK, re-install the blade retainer. 3. Re-install the blade and accelerator with the 7/16 20 blade bolt. Torque the bolt to 50 ft Ibs (68 Nm) 751.1.O490.
QUICK REFERENCE SECTION Specifications Special Tool Requirements. Troubleshooting Maintenance SERVICE SECTION Primer Start Carburetor. Fuelsystem Ignition System Rewind Starter. Engine Pivoting Zone StartBrake.
TROUBLESHOOTING 5-3 Engine Starts Hard Engine Runs Rich Engine Runs Lean Fuel Leaks From Carburetor 5-3 5-3 5-3 5-3 INTRODUCTION 5-4 Identification 5-4 Operation Governor 5-4 5-5 Servicing5-5 Removal Disassembly Cleaning and Inspection Assembly Installation Presetting the Governor Finalcheck Service Section 5-5 5-7 5-9 5-9 5-11 5-12 5-12
Fuel Leaks From Carburetor I Service Section 5-3
INTRODUCTION Identification The primer start carburetoris easily identifiedby the primer bulb mounted to the aluminum heat shield/ primer bracket and the black Minion carburetor body. This is a single circuit, fixed jet, non-adjustable carburetor manufactured by The Toro Company. 5 OperationAs the crankshaft rotates, the piston moves up and down in the cylinder. alternately creating pressure or a partial vacuum in the crankcase.
Governor The sail of the air vane governor is attached to the throttle valve of the carburetor. Air flow created by the rotating flywheel attempts to close the throttle. The governor spring resists this force and attempts to open the throttle. The balance between these two forces is the governed engine speed. I 751.2.5130.807 Governor Adjustment To change the RPMs ofthe engine you change the tension of the governor spring. Spring tensionis changed via an adjustable collar.
SERVICING (cont’d) Preliminary Check (cont’d Fuel cap vent- hole must not be plugged. Air filter- must be cleaned and oiled. 751.I ,0490.45 Crankcase seal-Crankcase seals must be installed properly andin good condition; torque value on the sump cover bolts must be correct. Carburetor flange gaskets and heat shield- must be installed correctly Exhaust ports- must not be restricted. Fuel- mixture must be fresh, not unknown, etc. If unknown, flush out. Governor air vane-must move freely.
4. Remove the throttle cable screw and nut from the throttle cable mounting bracket. 5. Detach the carburetor from the engine by removingthe two mountingscrews.Discard the two smaller carburetor gaskets on either side of the carburetor shield. Keep the heat shield/primer bulb bracket for later installation. 6. Disconnect the fuel line and the primer tube from the carburetor fittings.
SERVICING (cont’d) Removal (cont’d) 8. CAUTION: Avoid damaging the delicate governor spring during this step. Slide the white plastic control lever to either end of its adjustment and snap it to the locked position. This will help restrict its movement while you disconnect the throttle cable from the control lever. Disassembly Tools Required: Needle Nose Pliers Flat blade screwdriver 1.
3. Hold the governor collar on the carburetor and lift the air vane/throttleshaft out of the carburetor. Lift the collar and spring up, detaching the spring from the speed control lever. 751.I,0490.2 4. Turn the carburetor over and remove the four bowl retaining screws, the bowl gasket and the bowl. Discard the bowl gasket. 5.. Remove the fuel filter from the fuel nozzle. HINGE PIN 6. Remove the float hinge pin, the inlet valve needle assembly (withits clip) and the float.
SERVICING (cont’d) Disassembly (cont’d) 8. Remove the brass inlet fuel valve seat and discard. 9. Remove the nozzle and the high speed jet from the nozzle. Cleaning and Inspection 1. With the carburetor completely disassembled, thoroughly cleanall parts; do not soak the parts, use an aerosol carburetor cleaner. Inspect for wear or deterioration. Blow dryall carburetor passages with compressed air. CAUTION: If a tag wireis used, never enlarge or restrict any passageway in the carburetor. 2.
4. Install a new inlet valve needle and clip on the float. 5. Install the float assembly with a new float hinge pinin the bottomof the carburetor. Ensure the hingepin is positioned properly to keep the float level. The float should be free to move up and down easily in the carburetor body. 6. Adjust the float so the height is 15/32"to 17/32" (11.9 mm) 13.5from the bowl flange (without the gasketin place) to the top of the float. 4 7. Install the fuel filter over the nozzle. 8.
SERVICING (cont'd) of 9. Hook the governor spring into the bottom the governor collar. 10. Install the air vane and throttle shaft into the carburetor body by very carefully pushing the shaft through the collar into the carburetor body. 11. Push the throttle plate into the throttle shaft (the plate only inserts one way). 12. Holding the spring collar, hook the other end of the spring into the speed control arm. 13. Re-install the speed control lever and retainer.
Installation Tools Required: See "REMOVAL" Install new gaskets and the heat shield (removed in previous procedure) on the carburetor. The air cleaner element and its cover should not be in place at this time. Guide the air vane through the opening in the shroud base and attach the carburetor to the engine with the two mounting screws. Torque to 45-55 in Ibs (5.1 -6.2 N-m). Replace the spit cup, if used. To prevent any air leaks make sure the spitcup ( or two plugs) is(are) seated properly.
SERVICING (cont'd) 2. Use the tachometer to check engine speed; the normal high speed settingis 3050 150 RPM. Servicing theAir Filter 1. To remove the air filter, unsnap the wire holder, on the left side, from the cover. Then unsnap the cover from the clear plastic shell. Remove the cover and air filter element. 2. Clean and re-oil the air filter element according to the maintenance procedure, pages 4-3 and 4-4.
QUICK REFERENCE SECTION Specifications Special Tool Requirements. Troubleshooting Maintenance SERVICE SECTION Primer Start Carburetor. Fuelsystem Ignition System Rewind Starter. Engine Pivoting Zone StartBrake.
OPERATION..
OPERATION Fuel Tank The Toro V Engine uses a1.3 quart plastic fuel tank with a non replaceable 75 micron, intank, filter screen. The filteris welded in the bottomof the tank over the outlet fitting. The tank is mounted above the level of the carburetor and uses gravity to supply fuel through a.25" I.D. (6.35 mm) rubber hoseto the carburetor. The fuel hose is friction fitted to the tank outlet at one end and to the carburetor at the other end. The fuel tank is vented through an opening in the fuel cap.
SERVICE Tank Removal Tools Required Clamping Pliers Minimum 1.5 Qt (1.41ltr)Container #T25 Tow 1. Disassemble the starter rope “T”handle sufficiently to untie (or cut) the starter rope knot and release the rope from the handle ( the plastic rope-stop prevents the rope from rewinding completely into the starter). NOTE: To remove the fuel tank, you may either crimp the fuel hose and use the clamping pliers to remove the fuel hose from the carburetor.
CAUTION: Avoid fire and explosion. Store fuel in a container designed for gasoline and never smoke while working around gasoline. If you remove the fuel line from the tank outlet catch the fuel asit drains. Properly dispose of the fuel. Note: Always use a fresh supply of fuel when refilling the tank. Using a#T25 TORX driver, remove the three screws, with captive washers, that secure the fuel tank to the shroud assembly. 751.1.0490.
SERVICE (cont’d) Tank Installation Tools required: #T25 Tom 1. Fasten the tankto the engine with the three screws, with captive washers. 2. Connect the fuel line. 3. Refill the tank with a fresh gas/oil mixture and check the system for leaks. Fuel Storage Use clean, fresh, lead-free gasoline, including oxygenated or reformulated gasoline, with an octane ratingof 85 or higher. To assure freshness, purchase only the quantity of gasoline that can be usedin 30 days.
QUICK REFERENCE SECTION Specifications Special Tool Requirements. Troubleshooting Maintenance SERVICE SECTION Primer Start Carburetor. Fuel System 7 IgnitionSystem Rewind Starter. Engine Pivoting Zone StartBrake.
I TROUBLESHOOTING Process 7-3 7-3 SPARK PLUG Operation Service 7-4 7-4 7-4 CDPACK Advantages Operation Air Gap Adjustment Removal/lnstallation 7-4 7-5 7-6 7-6 FLYWHEEL Operation Removal Installation 7-2 7-4 7-6 7-6 7-7 7-8 Service Section /-
TROUBLESHOOTING Process Check the ignition systemin the following order: Spark plug (connection and wire condition) CD Pack (air gap, connections or spark) Flywheel (key and magnets) Use the following tableto aid in diagnosing the problem Cause engine dies. (NOTE: These symptoms may also caused be by fuel symptom problems).
SPARK PLUG Operation The spark plug ignites the fuel-oil mixture by producing a spark just before the piston reaches top dead center (TDC). A spark plug is typically constructed as shown. HEAD INSULATOR METAL SHELL COPPER CORE GROUND ELECTRODE LEG INSULATOR GAP GROUND ELECTRODE 751.2.5130.809 Service 1. Check the spark plug with the chart and replace, if necessary using the specifications shown. CAUTION: Do not clean the plug with a sand blaster. 7 2.
Electronic components are very small, have no moving parts, require no mechanical adjustments, and are not affected by wear as are mechanical devices. They deliver uniform performance throughout component life under adverse operating conditions. They canbe hermetically sealedso that they are unaffected by dust, dirt, or oilmoisture.
CD PACK (cont'd) Air Gap Adjustment Tools required: Air Gap Gauge (p/n 604659) 10 mm Socket 1. Rotate the flywheel until the magnets are directly adjacent to theCD Pack as shown. 2. Adjust the air gap by loosening the screws, inserting the gauge or a piece of .010" (.254 mm) shim stock, and tightening the screws. Removal/Installation Tools Required 1Omm Socket Flat blade screwdriver 1. Disconnect leads and remove the mounting screws. 2.
Removal Tools Required Piston Stop(p/n 677389) Puller (B&S #19165) or similar puller Soft Hammer 1/2” Socket 1. Remove the spark plug and install the piston stop. 2. Remove the shroud and fuel hoses. 3. Remove the flywheel nut.
FLYWHEEL (cont'd) Removal (cont'd) 5. Remove the key and checkits condition. 6. Replace the crankshaft and/or flywheel if the keyway is distorted or cracked. Replace the key if damaged. 7. Check the flywheel for wear and flywheel magnets for strength. Check the magnets by holding the flywheel up against a metal object. The magnets shouldhave a strong pulling force. Installation Tools Required: 1/2" Socket 1. Make sure the flywheel keyway is absolutely clean. 2.
QUICK REFERENCE SECTION Specifications Special Tool Requirements. Troubleshooting Maintenance SERVICE SECTION Primer Start Carburetor. Fuelsystem Ignition System 8 RewindStarter. Engine Pivoting Zone StartBrake.
Operation The rewind starter operates through a retainer/frictiondisc that causes two, spring-loaded, engagement dogs to extend from the rewind starter and engage the inside of the starter hub on the flywheel. The engagement dogs extend outward to make contact with the starter hub when the rope is pulled. When the engine starts, and the rope is released the starter dogs are retracted back into the center of the rewind mechanism, disengaging them from the starter hub.
QUICK REFERENCE SECTION Specifications Special Tool Requirements. Troubleshooting Maintenance SERVICE SECTION Primer Start Carburetor. Fuelsystem Ignition System Rewind Starter. Engine Pivoting Zone StartBrake.
ADVANTAGES DESCRIPTION 9-3 OPERATION 9-3 SERVICE TIPS Cylinder/Crankcase Halves 9-5 OilSeals CorePlugs Muffler Baffle ExhaustPorts Carburetor Gaskets 9-5 9-5 9-6 9-6 9-7 9-7 REMOVAL9-7 DISASSEMBLY9-11 INSPECTION AND REPAIR 9-12 REED VALVE SERVICE REASSEMBLY 9-14 Reinstalling External Components 9-17 9-2 Service Section P
ADVANTAGES DESCRIPTION Two-cycle engines have special advantages which make their use more practical in certain applications. Two-cycle engines are lightweight with an excellent power-to-weight ratio and can be operated in any position. They are also notably easy to maintain and service becauseof their uncomplicated design. REED VALVE The Toro Two-cycle V Engine used onToro rotary mowers is a reed valve design.
OPERATION (cont'd) The crankshaft continues its rotation and the As piston begins its travel toward the spark plug. it moves, the piston seals off the transfer port first, then theexhaust port. When both ports are sealed, the remaining travel compresses the air/fuel mixtureto prepare it for ignition. The travel of the piston towards the spark plug is called the compression stroke. REED VALVE The movement ofthe piston towards the spark plug also has an important effect in the crankcase.
The two-cycle engineis always well lubricated as long as the correct gas/oil mixture(using proper 2 cycle oil) is maintained in the fuel tank.Oil suspended in the fuelvapor adheres to all moving parts, keeping them continually coated, regardless of operating angle. SERVICE TIPS Cylinder/CrankcaseHalves The two halves are a matched pair and cannot be mixed. Check the cleaning and assembly procedures under Engine -Disassembly (pg 9-11) in this section.
SERVICE TIPS (con’t) Core Plugs Visually inspect for damaged or leaking plugs Muffler Baffle This item should be cleaned every 50 hours (maximum) to keep carbon from clogging the exhaust system (powerloss) and from entering the engine (piston scoring). 751.1.12071 Muffler Plate Screws Screws may have loosened due to vibration. 140 200 in.
Exhaust Ports Exhaust ports should be inspected every 50 hours and cleaned as necessary. Carburetor Gaskets Ensure that the air cleaner/carburetormounting in. Ibs screws are tightened to a torque 45-55 of (5.0 6.1Nm). Check for damaged or leaking gasket surfaces. Replace the gaskets if damaged. Carburetor gaskets on either side of the carburetor shield may be leaking or damaged causing air leaks into theengine (may cause power fluctuations).
REMOVAL (cont'd) 3. Remove the fuel tank (See Fuel Tank Removal, page 6-4). 4. Remove the shroud the starter comesoff with the shroud. 5. Remove the flywheel (See Flywheel Removal, page 7-7). _ _ I - 6. Remove the remaining bolts securing the shroud baseto the crankcase halves.
7 . Remove the brake plate assembly by removing one10 mm shoulder screw and one 3/8"washer-head screw. Place the assembly onthe mower deck and disconnect the ground wire that goes to the CD Pack. 8. Remove the CD Pack ( See CD Removal, page 7-6). 751.I,0490.80 9. Snap open the air cleaner cover (catch on left, hinge on right) and remove the air filter element. Pop out, and retain, the 2 plastic plugs(or spit cup) covering the carburetor screws.
11. Remove the7/16-20 blade bolt that secures the blade, blade retainer and accelerator to the engine shaft. Use heavy duty gloves to hold the blade while removing the nut. Set the parts aside 12. Tools Required Compression Pliers (p/n303857) Wrist Pin Knockout Tool (602884) TOW E-12 Flat blade screwdriver 1. Remove the four crankcase cap screws with a TOW E-12 socket and separate the halves using a screwdriver.
2. Remove the entire crankshaft assembly and discard theoil seals. Carefully remove theHSH (hex socket head) cap screwsto remove the connecting 32 rod cap and the split bearing liner. The needle roller bearings are under the split bearing liner and will be loose. Careful account forall of them. r 3. Remove the piston and rod assembly; separate the assembly,if necessary, using a compression pliers on the retaining ring. Use the wristpin knockout tool to punch out the wrist pin.
INSPECTION AND REPAIR (CONT'D) 2. Check rings for sticking. Remove and check rings for wear (e.g. ring end gap) or damage; replace the rings if questionable. 3. Clean and inspect the piston, including the ring land and wrist pin snap ring grooves. Check all parts for wear or damage and replace if questionable. 4. Clean the crankcase surfaces with Gel Seal and Gasket Remover. 5. Check that the ring end gapis between .006" and .016"(.152 .406mm) with .030" (.762mm) as the wear limit.
6. Replace the core plugs if leaking, using Screw Lock on the outside surfaces. CAUTION: Do not attempt to clean anyhole with a drill bit. REED VALVE SERVICE Tools & Supplies Required: Loctite 271 Carburetor Solvent Feeler Gauge These assemblies permit fuel mixtures to enter the crankcase on the compression stroke and to trap fuel mixture in the crankcase on power strokes. Check the clearance between the tip of the reed and the plate; replace the reeds if the clearance is more than .004"(.l mm). 751.I.
REASSEMBLY Tools & Supplies Required Loctite 271 Loctite 515 Gasket Maker Piston Stop (p/n 677389) Ring Compressor (p/n 609967) Seal Driver (p/n 608976) 1. Secure the wrist pin using the snap ring. Make surethe square edge of the snap ring faces out and the ring opening faces up (toward the topof the piston). 2. Install the pressure back piston ring in the top groove with the bevel facing up; The square cut ring goes second and has no top or bottom orientation. Stagger the ring gaps.
4. Lubricate and assemble the needle bearings to the crankshaft and install the crankshaft. 6. Oil the parts anduse the piston stop and ring compressor to install the piston with the “BTM”mark facing toward the exhaust ports. NOTE: The letters “BTM”were omittedon some engines. However the small “rectangle” should still be visible through the ports. 751.1.1207.
REASSEMBLY (cont’d) 7. Thinly apply Loctite515 or Three Bond 1104 gasket makerto the crankcase cover sealing surface. Be careful not to get sealant on the bearings or seals. 8. Carefully align thetwo crankcase halves using the alignment pin and its matching hole; press thetwo halves together. 9. Torque the hex washer-head screws to a total of 110 in. Ibs (12.5 NOTE: Tighten the screws in increments of 20 in Ibs (2.26 Nm ) while checking that the crankshaft turns freely. 10. Install new oil seals.
Reinstalling External Components 12. Reattach the flywheel brake system. 751.1.0490.28 13. Clean the crankshaft and flywheel hub and install the flywheel (see flywheel installation, page 7-8). 14. Install the carburetor and governor assembly (see page5-11). 15. Install the starter and shroud assembly and starter handle (see page9-7). Reconnect the fuel lines and electrical system leads. Test run the engine. ~- 751.1.1207.
QUICK REFERENCE SECTION Specifications Special Tool Requirements. Troubleshooting Maintenance SERVICE SECTION Primer Start Carburetor. Fuelsystem Ignition System Rewind Starter. Engine Pivoting Zone StartBrake.
INTRODUCTION. 10-3 OPERATION.
INTRODUCTION 2 Primary Safety Criteria 1 Two-step Operation to start 2. Blade stops in three seconds In 1982 the federal government mandated that all consumer walk behind mowers with a cut25" of (63.5cm) or less,be equipped with a safety blade stopping device. There are two primary criteria which these devices must meet: A two-step operation must be performed in order to start the blade rotating. The blade must come to a stop within three seconds of the operator leaving the operator's position.
OPERATION (cont'd) Switch leads are connected to the primary side of the coil and to the ground. When the switch is closed, coilis grounded. This action prevents the coil from producing the high voltage necessary to generate spark. When the switch is open, the ignition coil produces spark. 751.2.5130.819 Stopping the engine and blade is accomplished by meansof a brake thatis applied to the bottom of the flywheel.
1. If the engine and blade are taking more than 3 seconds to stop when the blade control bail is released, inspect the brake pad for excessive wear and replaceif necessary. Note that the brake pad and the brake plate are replaceable only as an assembly. Disconnect the cable from the control bail on the handle 2. To reduce the pressure of the spring between the brake mounting plate and brake plate, squeeze the tabs of the brake cable that holdit in place at the brake mounting plate.
DISASSEMBLY (cont’d) /7 4. Remove the 10 mm shoulder screw to remove the brake plate and brake pad attached toit. 5. If the ground strap or any partof this assembly requires replacement, removethe second screw to remove the brake mounting plate from the engine. ASSEMBLY Tools Required 10mm Sockets Needle nose Pliers 1.
3. Slide the cable into the narrow slot on the brake mounting plate and then push the cable into the hole making sure the tabs lock into the bracket. 4. One endof the compression spring has a hook shapeto it; that end hooks over an indentation in the brake plate. Squeeze the compression spring and slip it over the cable between the brake mounting plate and brake plate. 751.1.0490.70 5. Reattach the cable to the control bail on the handles 751.I,0490.
ASSEMBLY (cont’d) of the cable into the 6. Insert the ball end vertical slotof the brake plate. 7. Operate the blade control bail to verify that the brake mechanism stops the blade within three seconds.
QUICK REFERENCE SECTION Specifications Special Tool Requirements. Troubleshooting Maintenance SERVICE SECTION Primer Start Carburetor. Fuelsystem Ignition System Rewind Starter. Pivoting Zone StartBrake.
Table Of Contents - Power Head Exploded View. ............................... A-3 ........................ A-4 Ignition and Exhaust.Exploded View Starter and Primer Start Carburetor .Exploded View. . Primer Start Carburetor Assembly Exploded View. n ........... A-5 ............
- - Power Head Exploded View 5 Ref. U 20 I 15 3 1 11 1 - Oil Seal (2) 2 - Upper Main Bearing (Narrow) 3 - Split Liner (2) 4 - Bearing 5 - Connecting Rod Assembly 6 - Retaining Ring 7 Wrist Pin 8 - Piston 9 - PistonRing 10 - Top Piston Ring 11 - Cylinder & Crankcase Assembly - 12 - Core Plug (4) 13 - Dowel 14 - Needle Bearing (Wide) 15 - Slotted Head Screw(2) 16 - Reed Backup Plate 17 - Carburetor Reed 18 - Washer Head Hex.
- Ignition and Exhaust Exploded View 19 18 17 16 1 12 1 - Shoulder Screw 2 - Brake Plate Assembly 3 - Screw 4 - Brake Mounting Plate 5 - Hex. Washer Head Screw (2) 6 - CD ignition Pack 7 - Spark Plug (Champion RJ12C) 8 - Exhaust Gasket 9 - Muffler Cover 10 - Screw (3) . .
- Starter and Primer Start CarburetorExploded View 20 19 16 1 - Shroud Assembly 2 - Screw (4) 3 - Nut 4 - Lockwasher 5 - Starter Hub 6 - Flywheel Assembly 7 - Shroud Base 8 - Key 9 - Carburetor Gasket (2) 10 - Carburetor Heat Shield & Primer Mount r'\ 11 - Primer Bulb 12 - Primer Body 13 - Primer Hose 14 - Fuel Shield 15 - Air Filter 16 - Air Filter Cover - Screw (2) 18 - Carburetor Assembly 19 - Screw (3) 20 - Rope Appendix A-5
Primer Start Carburetor Assembly Exploded View I n 6 i 7 1 Screw (2) Gasket Main Nozzle Filter Screen Float Carburetor Bowl 10 Screw (4) 11 Float Pin 12 Main Jet 5 6 7 8 9 13 Retainer 14 Inlet Needle 15 Inlet Seat 16 Carburetor Body 17 Throttle Plate Throttle Spring 19 Air Vane Collar 20 Air Vane 21 Cable Bracket 22 Lever 23 Retainer i i A-6 Appendix 10
Carburetor Troubleshooting Engine Starts Hard EngineRunsRich Engine Runs Lean Fuel Leaks From Carburetor Introduction Identification Operation Governor Servicing Removal 5-5 Disassembly Cleaning and Inspection 5-9 Assembly Installation Presetting the Governor Final Check 5-12 5-3 5-3 5-3 5-3 5-3 5-4 5-4 5-4 5-5 5-5 5-7 5-9 5-1 5-12 Air Gap Adjustment Removal/lnstallation 7-6 Flywheel Operation Removal Installation 7-8 Maintenance Air Filter Cleaning Spark Plug Spark lug Gap Spark Plug Torque Exhaust Syst
