TORO/LAWN-BOY TWO STAGE SNOWTHROWER DRIVE SYSTEMS MANUAL Table of Contents – Page 1 of 2 AUGER GEARBOX SERVICE GENERAL INFORMATION AUGER GEARBOX LUBRICANT GEARBOX REMOVAL PRIMARY METHOD — MINIMUM DISASSEMBLY SECONDARY METHOD — TRACTION AND AUGER HOUSINGS SEPARATED: TORO MODELS 38065 AND 38080 ALL OTHER MODELS INSTALLATION AUGER GEARBOX DISASSEMBLY / SERVICE FAILURE ANALYSIS GEARBOX ASSEMBLY BELTS, CONTROLS AND LINKAGES INTRODUCTION REPLACING THE AUGER/IMPELLER DRIVE BELT REPLACING THE TRACTION BELT REPLACIN
TORO/LAWN-BOY TWO STAGE SNOWTHROWER DRIVE SYSTEMS MANUAL Table of Contents – Page 2 of 2 TRACTION DRIVE SYSTEMS - CONTINUED DISASSEMBLY LAWN-BOY MODELS 28230, 23231 TORO MODELS 38051, 38052, 38054, 38056, 38062, 38063, 38064, 38072, 38073 ASSEMBLY LAWN-BOY MODELS 28230, 23231 TORO MODELS 38051, 38052, 38054, 38056, 38062, 38063, 38064, 38072, 38073 ASSEMBLY TIPS ASSEMBLY STEPS DISASSEMBLY TORO MODELS 38066, 38078, 38083, 38084, 38086 ASSEMBLY TORO MODELS 38066, 38078, 38083, 38084, 38086 SUB ASSEMBLY REPAIR
2-Stage Snowthrower Drive Systems Service Manual
About This Manual This manual was written expressly for the Toro and Lawn-Boy servicing dealer. The Toro Company has made every effort to make the information in this manual complete and correct. This manual was written with assumption that the reader has basic mechanical knowledge and skills. This book contains material covering the Toro and Lawn-Boy brand 2-Stage Snowthrowers produced from 1990 to 2002, and may be specified for use on products built before 1990 or after 2002 that are similar in design.
Contents AUGER GEARBOX SERVICE . . . . . . . . . . . . . GENERAL INFORMATION . . . . . . . . . . . . . . . . AUGER GEARBOX LUBRICANT . . . . . . . . . . . GEARBOX REMOVAL . . . . . . . . . . . . . . . . . . . Primary Method — Minimum Disassembly . . . . . . . . . . . . . . . . . . . . . . Secondary Method — Traction and Auger Housings Separated: Toro Models 38065 and 38080 . . . . . . . . . . . . . . . . . . Secondary Method — Traction and Auger Housings Separated: All Other Models . . . . . . . . . . . . .
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Introduction This manual will cover service to the auger and traction drive systems on small and intermediate frame 2 stage snowthrowers. Service information for Power Shift snowthrowers is contained in manual 492-0354.
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Chapter 1 — Auger Gearbox Service GENERAL INFORMATION The manual takes a systems approach. There are two versions of the auger gearbox and three versions of the traction drive system used among the various 2-stage models. For information on the auger drive or linkage adjustments see the section titled Belts, Controls and Linkages. The lubricant level in a gearbox should be checked prior to each season. Figure 2 AUGER GEARBOX LUBRICANT Two different lubricants are used in the various models.
Auger Gearbox Service Primary Method — Minimum Disassembly 3. The following steps apply to all models. 1. In the center of each side plate are either two or four cap screws (depending on the model). These go into the bearing that supports each side of the auger. Remove the cap screws (Figure 5). Remove the belt cover. Loosen the belt guide on the engine crankshaft and remove the auger belt. DO NOT bend the belt guide out of the way (Figure 3). Figure 5 4. Figure 3 2.
Auger Gearbox Service 5. Loosen the rear and remove the front capscrew securing the idler arm to the chassis. 1 1 2 Figure 9 1. Pulley 2 7. Figure 7 1. Loosen 6. M-3331 2. Remove Begin to pull the auger assembly out to the front. Note: The auger pulley and key have not yet been removed. However, if you pull the auger slightly forward, it will make it easier to slide the pulley off the end of the impeller shaft. Once the pulley is out of the way, remove the key (Figure 8 and Figure 9). 2768-023 2.
Auger Gearbox Service 9. The auger flighting is attached to the auger shaft with one bolt and locknut. Reach through the holes in the drum augers to access. On models without drum augers, the bolts are easily accessible (Figure 11). 2. Drain the fuel and oil and stand the machine up on its auger. Support or brace to prevent tipping (Figure 13). 1 Figure 13 Figure 11 MVC-533 3. 1. Access hole 2768-027 Disconnect the chute crank rod at the auger (Figure 14).
Auger Gearbox Service 5. There are 4 locknuts in the forward part of the housing. These are on studs from the auger. Remove the locknuts. The traction assembly will now lift straight up off the auger assembly (Figure 15). Figure 17 3. 1 Figure 15 2768-025 1. Locknut 6. MVC-534 Place a block of wood under BOTH the auger and traction assembly to support them when the connecting cap screws are removed.
Auger Gearbox Service INSTALLATION Installation of the auger assembly into the auger housing can be done whether the auger housing and traction assemblies are connected or not. There is no significant time savings to either sequence. 1. All self-aligning bearings (sometimes called the flange bearings) MUST be installed loosely. All models have one next to the auger drive pulley and some use 2 more supporting the auger output shafts.
Auger Gearbox Service AUGER GEARBOX DISASSEMBLY / SERVICE Once the auger gearbox assembly is removed from the housing the repair process is the same for all models. The only variables are what type of lubricant is used (see the chart on Introduction page 1), whether the impeller is removable from the shaft (on some models the impeller is welded to the shaft) and how the gearbox case halves are sealed. Figure 23 4. Auger gearbox disassembly: 1.
Auger Gearbox Service 6. Clean the output shaft and slide the case halves off. Remove the seals from the case halves and discard the seals. 7. Clean and inspect the bushings in the case halves. If they are damaged or worn, press them out of the case halves at this time. 8. Slide the worm gear off the shaft. Depending on the model, there will be one or two woodruff keys between the gear and the shaft. Refer to the parts manual for your specific machine. 9.
Auger Gearbox Service Failure Analysis GEARBOX ASSEMBLY There are some misconceptions regarding these gearboxes that result in incorrectly identifying the causes of failure. 1. The square cut ring on the impeller shaft is not really a seal. It is a wiper ring that has a tendency to pull down to the shaft when the shaft begins to turn. The bushing next to the ring really deflects most of the oil that is thrown towards that area. The loose fit provides a vent for the case (Figure 27).
Auger Gearbox Service 3. Insert the keys into the shaft and slide the large worm gear into place. Note: There is a large letter “R” and an arrow on one side of the gear. This gear MUST be installed such that the R and the arrow are on the right hand side and the arrow is pointing forward (Figure 30). This is a two piece gear that is bonded together. If it is installed backwards, the forces try to separate the gear and can result in failure. Figure 31 1. 2. 3. 4. 5. 6.
Auger Gearbox Service 7. Apply a VERY light coat of Loctite™ Blue #242 or quivalent to the outer diameter of the bearing. Loctite™ should not squeeze out when everything is tightened (Figure 33). 10. All models. Apply a light coat of oil or anti-seize to the gear case screws. Tighten them in an X pattern to 120 in/lbs. (15kg/m) (Figure 34). Note: Some models have 8 gear case screws; others have 9. 9 5 3 2 1 7 8 Figure 33 8. 9. 2773-059 Some models use a gasket and some do not.
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Chapter 2 — Belts, Controls and Linkages INTRODUCTION All models use two belts. One to drive the auger and a second to drive the traction system. The auger drive uses a combination idler and brake to engage the belt for driving and to disengage the belt and apply the brake for stopping. The traction drive uses a constantly tensioned belt. The clutching and shifting are done through the drive plate and friction disc. REPLACING THE AUGER/IMPELLER DRIVE BELT Figure 36 1.
Belts, Controls and Linkages 7. The belt guide must be checked and adjusted. With the engine off, engage both the auger and traction controls. Adjust the belt guide so that there is approximately 1/8 inch (.3 cm) clearance between the belt guide and the belt. 3. Move auger drive control to DISENGAGE and wheel drive control to N, neutral. Next, remove auger drive belt from engine pulley and large auger/impeller pulley. 4. Loosen two capscrews (securing traction idler arm to front of engine.
Belts, Controls and Linkages Replacing the Traction Belt — Lawn-Boy Models 28230, 28231 and Toro Models 38051, 38052, 38054, 38056, 38062, 38063, 38064, 38072, 38073 5. Tip the snowthrower forward and block it so it cannot fall. 6. Remove the four screws that secure the bottom cover to the frame and remove the cover (Figure 41). When the traction drive belt becomes worn, stretched, oil-soaked, or otherwise damaged, replace the belt. 1.
Belts, Controls and Linkages 11. Install a new belt around the large traction pulley. 12. Loop the belt over the engine pulley, ensuring that the belt is on the inside of the belt guide (Figure 40). 13. Tip the snowthrower forward and block it so that it cannot fall. Replacing the Traction Belt — Lawn-Boy Model 28232 and Toro Models 38053, 38066, 38078, 38083, 38084, 38086 When traction belt (Figure 43) becomes worn, oil– soaked or otherwise damaged, belt replacement is required. 14.
Belts, Controls and Linkages 3. Loosen auger brake arm assembly by loosening rear screw and removing front screw (Figure 45). Figure 45 1. 2. Rear screw Front screw 3. 13. Reinstall engine pulley sheave, washer, lock washer, and crankshaft screw. Make sure the indexing rib in the engine pulley sheave is aligned with the indexing notch in the center engine pulley (Figure 46). M-2678 Idler pulley spring 4. Remove idler pulley spring (Figure 45). Let brake arm assembly hang free but out of the way. 5.
Belts, Controls and Linkages 15. Reinstall (2) screws that secure auger brake arm assembly. Make sure tabs fit into holes in left side of machine (Figure 48). 17. Check and adjust auger drive linkage. Refer to steps 5–7 of "Auger/Impeller Drive Control Linkage — All Other Models" on page 2 - 8. 18. Reinstall idler pulley spring. 19. Reinstall belt cover with (3) screws. Figure 48 1. M-2678 20. Make sure that auger and impeller are not rotating when auger/impeller control lever is disengaged.
Belts, Controls and Linkages CONTROL AND LINKAGE ADJUSTMENT Note: Before making any control adjustments, verify that the handles are secured to the traction frame. If the handles move at all, the linkages will not maintain adjustment. Adjusting Auger/Impeller Drive Belt If auger slips, which means the auger drive belt is slipping, an adjustment is required. When a new auger/ impeller drive belt is installed, an adjustment may also be required. 1.
Belts, Controls and Linkages Auger/Impeller Drive Control Linkage — All Other Models 6. Remove the belt cover (refer to "REPLACING THE AUGER/IMPELLER DRIVE BELT", page 2 - 1, steps 1-2). Compress the auger/ impeller control lever and check that the slack is removed from the auger drive belt when the lever is 1-2 inches (2.5-5 cm) above the handgrip (Figure 54). 7. Adjust the clevis or two flange nuts to obtain this dimension, then tighten the two nuts or jam nut securely (Figure 55).
Belts, Controls and Linkages ADJUSTING TRACTION CONTROL 3. Adjusting the Traction Control — Toro Models 38065, 38080, 38085 1. Move wheel drive control lever onto the hump between N and 1 (Figure 58). Hold wheel drive control lever in this position — on hump. Note: Lever must be held against the hump, not in the N or 1 position. Move wheel drive control into No. 1, 1st gear.
Belts, Controls and Linkages Adjusting the Traction Control — 824XL (Toro Models 38066, 38078, 38083, 38084, 38086 and Lawn-Boy Model 28232) 1. Slide spring onto bottom of traction control rod (Figure 59). Figure 61 1. 2. Traction control lever Handgrip 3. 4. Figure 59 1. 2. Traction control rod Spring 3. M-2665 Flange lock nut 2. Thread a flange lock nut (flange side up) onto bottom of traction control rod below spring. 3.
Belts, Controls and Linkages ADJUSTING THE TRACTION ROD — LAWN-BOY MODELS 28230, 28231 AND TORO MODELS 38051, 38052, 38054, 38056, 38062, 38063, 38064 1. Tighten the two flange nuts finger tight. 4. Move the speed selector (Figure 64) into third gear. Note: If the speed selector does not move into third gear, adjust the speed selector before continuing. See “ADJUSTING THE SPEED SELECTOR” on page 2 - 12.
Belts, Controls and Linkages ADJUSTING THE SPEED SELECTOR If the snowthrower is slow, the No.1 speed selection has no speed, or the speed selector does not move into the No. 3 speed selection, adjust the speed selector linkage. 1. Disconnect the wire from the spark plug and make sure that the wire does not contact the spark plug. 2. Tip the snowthrower forward and block it so that it cannot fall. 3. Remove the four screws that secure the bottom cover to the frame and remove the cover. 4.
Chapter 3 — Traction Drive Systems INTRODUCTION All models use some variation of a friction drive. The engine drives a belt, which causes a drive plate(s) to rotate. As this belt is constantly tensioned, the belt and drive plate turn whenever the engine is running (Figure 67). 1 Figure 68 1. Figure 67 1 2773-014 Clutching and speed control is accomplished by moving the friction wheel. When declutched the friction wheel is not contacting the drive plate (Figure 68).
Traction Drive Systems TROUBLESHOOTING THE TRACTION DRIVE — ALL MODELS Drive slipping: 1. Verify adjustment of traction drive linkage. 2. Make sure the engagement spring and idler spring are in place and undamaged. 3. Verify that the drive plate and friction wheel are clean and free of grease or oil. Clean with alcohol or something that does not leave a residue. 4. Replace the friction wheel if worn. The most convenient method of working on the traction drive is to stand the machine up on the auger.
Traction Drive Systems 6. The axle can now be removed from the chassis. Inspect the gear, the roll pin, and the areas where the bearings contact the axle for damage or severe wear. Remove the thrust washers from either end of the axle. The purpose of the roll pin and thrust washers is to limit the side to side movement of the axle. 7. Disconnect the two clevis pins on the shift linkage rods. 8. Next to the friction wheel is a large eyebolt, which is connected to the shift linkage (Figure 74).
Traction Drive Systems E. If the eyebolt, or traction drive hub is to be replaced, remove the snap ring on the hub (Figure 78). ASSEMBLY — TORO MODELS 38065, 38080, 38085 Preparation 14. Before assembling something with a new bushing, wipe the bushing with a clean shop towel. This should remove any debris that might have gotten into the bushing during shipping and storage. 5 15. These are oil-impregnated bearings.
Traction Drive Systems Assembly 1. Slide the pillow block bearing, reverse plate (with the hub side away from the pulley), thrust washer, bearing (hub side facing the reverse plate), thrust washer, and spacer onto the drive shaft. Drive the roll pin through the spacer and shaft. Secure the reverse plate with the cap screw and locknut (Figure 80). Figure 81 3 1 5 2 4 6 Figure 80 1. 2. 3. Pillow block bearing Reverse plate Pulley/forward plate 4. 5. 6.
Traction Drive Systems 4. F. Hook the long end of the spring in the hole in the left front corner of the frame (Figure 84). If the pivot assembly was repaired, now is the time to assemble it. A. Secure the friction wheel to the hub with four cap screws and locknuts. If the locknuts are worn, apply a drop of Loctite™ Red #271 or equivalent to the threads. B. Slip a slider ring on either side of the eyebolt and slide it on the hub. Install the spacer and snap ring.
Traction Drive Systems 6. Next, tension the pivot assembly. With the unit upright, use a screwdriver to stretch the traction spring and hook it into the hole provided (Figure 86). Figure 86 7. DISASSEMBLY — LAWN-BOY MODELS 28230, 23231 AND TORO MODELS 38051, 38052, 38054, 38056, 38062, 38063, 38064, 38072, 38073 1. Drain the gasoline and oil. 2. Remove the belt cover. Loosen the belt guide, do not bend. Remove the auger and traction belts (Figure 88).
Traction Drive Systems 6. Remove 4 self-tapping screws that secure the axle bearings to the traction frame. Lift the axle and bearings out (Figure 89). Slide the bearings and thrust washers off the axle. Figure 89 9. To remove the traction engagement assembly, remove the retaining ring on the left side of the frame. Note: Some older models use a cap screw through the side plate into the end of the shaft. Slide the shaft to the side and it will disengage from the chassis (Figure 91). 2773-074 7.
Traction Drive Systems 11. If it is necessary to remove the gear quadrant, it is best to just remove the two self-tapping screws that secure the gear quadrant mount to the traction frame. The gear quadrant and gear quadrant frame can then be separated easily (Figure 93). 16. To remove the front frame, pulley, and drive plate assembly, remove the two shoulder bolts that the frame pivots on. The assembly will then lift out of the chassis (Figure 95). 1 Figure 95 Figure 93 1.
Traction Drive Systems ASSEMBLY — LAWN-BOY MODELS 28230, 23231 AND TORO MODELS 38051, 38052, 38054, 38056, 38062, 38063, 38064, 38072, 38073 Assembly Tips 1. Assembly Steps 1. Assemble the hub to the front frame using 4 screws. 2. Install the snap ring onto the pulley and shaft. Assure the sharp edge of the snap ring faces towards the pulley (Figure 98). Before assembling something with a new bushing, wipe the bushing with a clean shop towel.
Traction Drive Systems 5. Install the friction plate spring into the front frame assembly. Note some models just have a hole in the frame. Others have a tab bent outward to hook the spring into (Figure 100). Hook the lower end of the spring into the notch in the traction frame. 7. Lightly oil the hex shaft. Insert the hex shaft from the left side, non-threaded end first. Slip the shaft through the left side of the sliding bracket (Figure 102). Figure 102 Figure 100 6.
Traction Drive Systems 11. Slide the wheel and hub on the hex shaft with the friction wheel closest to the sliding bracket. Install the locknut, holding the hex shaft with an openend wrench (Figure 104). 1 Figure 106 MVC-866 15. Connect spring to hole in front of pivot assembly (Figure 107). Figure 104 MVC-720 12. If the receiver cam has been removed, install it now. 1 Figure 107 2773-084 16. Assemble the gear quadrant and the mounting bracket. (Figure 108). Figure 105 1.
Traction Drive Systems 17. Install the friction wheel and sliding bracket. The friction wheel should be on your left (Figure 109). 19. Install a thrust washer and bearing on each end of the axle. Locate the holes and secure the axle bearings to the frame (Figure 111). 1 2 Figure 109 1. Gear quadrant 2. 2773-081 Sliding bracket Figure 111 The gear quadrant must be free to pivot. The first tooth on the quadrant should go into the hole in the right side as shown in Figure 110. 773-074 20.
Traction Drive Systems 21. If the lower traction rod was removed, reinstall it now. Slide the end through the traction bracket then install the spring and locknut. Turn the locknut on until the spring is compressed to approximately 2 ¼” (5.7 cm) long (Figure 113). 1 1 Figure 114 1. 4. Figure 113 2773-010 0054-007 Traction shaft bearings To remove the upper traction shaft and friction wheel assembly, disconnect the master link in the chain.
Traction Drive Systems 6. To remove the intermediate shaft, loosen the retaining bolts and remove the chain. Loctite™ Red #271 is used to secure these bolts. Remove the shaft (Figure 116). 8. Disconnect the friction plate disengagement spring (in the upper left corner of the traction housing) (Figure 118). 2 3 1 Figure 118 Figure 116 7. 1. 2. 0054-009 To remove the axle and friction plate assembly, disconnect the traction idler spring (shown just below the right side axle bearing) (Figure 117). 9.
Traction Drive Systems ASSEMBLY — TORO MODELS 38066, 38078, 38083, 38084, 38086 4. Reverse the process for assembly. See the following tips for special information. 1. Lightly grease the axle gear. Spread about ½ teaspoon of #2 general-purpose grease around the circumference of the gear (Figure 119). Excess grease will just fling off when the machine is driven. When installing the traction shaft and friction wheel, the bearings must be aligned. Loosely install the assembly into the chassis.
Traction Drive Systems SUB ASSEMBLY REPAIR — TORO MODELS 38066, 38078, 38083, 38084, 38086 This section will cover the disassembly and repair of the traction shaft/friction wheel and the axle and friction plate assembly after they have been removed from the chassis. Traction Shaft/Friction Wheel Disassembly 1. With the assembly out and on the bench, the bearings will just slide off the shaft (Figure 122). Figure 122 1. 2. 3. 4. 5. 6.
Traction Drive Systems 6. There are 2 versions of the hub and slider. The early models use a normal thrust washer on either side of the slider. Later models use a thrust washer with an internal key that fits into a keyway cut into the shaft portion of the hub. This keyed version is current; if the older hub is ordered, you will automatically get the new version (Figure 123). Axle and Friction Plate Disassembly 1. The pulley and shaft go through the bearing hub and the drive plate screws on.
Traction Drive Systems Axle and Friction Plate Assembly 3. Remember the threads on the pulley and shaft and the drive plate are left hand. Tighten firmly. Assemble in reverse order. The following are notes to assist you: 4. Install the bearings on the friction plate frame. Do not tighten yet. 5. After the axle is installed, rotate the axle and firmly strike each bearing with a rubber mallet. This helps align the bearings with the axle. Secure the bearings to the frame. 1.
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