2. C H A P T E R 22 Snow Throwers

3. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Safely operate and service snow-throwing equipment. List important purchasing considerations for snow throwers. Identify major parts of walk-behind snow throwers. Make adjustments to snow throwers. Properly maintain snow-throwing machines. Learning Objectives

4. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Safety Precautions Be aware of dangers inherent in these machines Understand the specific make and model before servicing or operating Consult owner’s manual or service manual when in question Never make adjustments when engine is running Disengage all clutches before starting engine Make sure all hardware is tight

5. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Safety Precautions Clear work area of objects that may be thrown If object is hit, stop and inspect machine Adjust skid shoes to clear gravel surfaces Do not leave running machine unattended Make sure to have good footing Avoid sudden stops and starts Do not run engine in confined area

6. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Safety Precautions Keep hands and feet away from rotating parts Use grounded receptacle for starting Do not overload machine capacity Disengage auger when machine is not in use Do not change governor speed settings

7. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Small Snow Throwers Cleaning width 16  –20  Two-cycle engine, approximately 3 hp Recoil starter Electric start optional Single-stage snow throwers –Blades operate like paddles

8. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Single-Stage Snow Throwers (The Toro Co.)

9. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Midsize Snow Throwers Two- or four-cycle –Engines range from 3–8 hp May be single-stage or two-stage –Helical-shaped augerauger –In a two-stage snow thrower, auger feeds the snow into high-speed blowertwo-stage snow thrower May be self propelled May have pneumatic tires Electric start

10. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Two-Stage Snow Throwers (Simplicity Manufacturing Inc.)

11. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Heavy-Duty Snow Throwers Four-cycle engines –8–20 hp Same features as midsize throwers, but are heavier and clear wider paths Can throw snow as far as 40 Some models feature weight-shifting capabilities

12. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Engine Controls (Simplicity Manufacturing Co.)

13. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Snow Thrower Controls (Simplicity Manufacturing Co.)

14. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Operator Presence Controls Stops auger from turning when drive lever is released If drive control lever is engaged, auger control lever stays engaged without holding it –When drive control lever is released, auger control lever is released and auger stops –Engine continues to run

15. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Electric Start Systems Convenient for larger engines and in cold conditions Engines with electric starters also have recoil starters –When supplemental electrical power is not available, recoil starter can be used Connected to 110V ac grounded outlet Current reduced to 12V dc for the starter motor

16. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Drive System Two driving systems: –One system drive auger in single stage machines or auger and blower in two-stage machines –Second system drives wheels and tracks on self- propelled snow throwers Transmissions may consist of gears, belts, chains or a combination of the three

17. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Auger Gearbox (The Toro Co.)

18. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Track Systems Rubber tracks used on some heavy-duty modelsRubber tracks –Provide exceptional traction –Can be engaged singularly for steering –Clutch levers provided on each handle to control direction of travel

19. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Track Systems (MTD Products, Inc.)

20. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Track System Service With extensive use, tracks may wear out Chain drive that powers track may require replacement Track adjusters allow loosening or tightening of tracks –Tension on both sides should be adjusted properly and equally

21. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Track Chain Replacement 1.Support unit so track is off ground 2.Loosen nut on track tension adjusters 3.Roll track off idler and drive wheel assembly 4.Remove chain by disconnecting master link 5.Reassemble in reverse order with a new chain or track

22. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Master Link (Simplicity Manufacturing Co.)

23. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Track Tension Adjustment 1.Disconnect spark plug wire and ground against engine 2.Drain fuel tank 3.Tip snow thrower so it rests on auger housing 4.Loosen track adjuster bolt 5.Insert screwdriver between tab on track adjuster to tighten or loosen track 6.Tighten track adjuster bolts

24. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Track Lever Lock Selects position of auger housing and method of operation –Transport –Normal snow –Packed snow

25. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Skid Shoes Establish height of scraper barscraper bar Located at bottom edge of auger housing Absorb wear Slotted holes allow adjustment –On smooth surfaces, scraper bar should scrape surface or clear by 1/8  –On gravel surfaces, scraper bar should be high enough that it will not pick up gravel or debris

26. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Skid Shoe (Deere & Co.)

27. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Skid Shoe Adjustment Procedure 1.Park snow thrower on hard, smooth surface 2.Stop engine and remove key 3.Remove wire from plug and ground to engine 4.Check tire air pressure 5.Put block of desired height under scraper bar 6.Loosen adjustment nuts, lower skid shoes to surface, and tighten nuts

28. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Engine Starting 1.Turn fuel valve on 2.Insert ignition key and turn to Run or Start 3.Move throttle to Fast position 4.Close choke and press primer several times (do not choke or prime warm engine to restart) 5.Pull starter handle or push starter button 6.Turn off choke and set throttle to Slow 7.Allow engine to warm up at slow throttle before operating the snow thrower at full speed

29. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Snow Throwing The following procedure is for one particular model. Procedures vary from model to model. 1.Rotate chute to desired direction 2.Set speed selector to desired forward speed 3.Press and hold auger control lever 4.Press and hold traction drive control lever 5.Release drive control lever and move speed selector to select desired speed and direction

30. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Preventing Freeze-Up 1.Before stopping engine, pull starter rope out several times and allow it to rewind slowly 2.Stop engine 3.Disconnect plug wire and ground on engine 4.Brush snow and ice from snow thrower 5.Reconnect plug wire

31. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Servicing Augers Made in two halves Center driving members are hollow tubes installed over solid shaft Shear bolts or shear pins connect tubes to shaftShear bolts –Bolts or pins will shear to protect auger and gearbox from damage resulting from obstruction –Replace sheared bolts or pins with bolts or pins with the same shear strength

32. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Snow Thrower Lubrication Periodic lubrication will extend useful life Some parts require the application of oil, while others require grease –Lubricate external parts with medium weight oil –Use a grease gun to apply grease to grease (zerk) fittingsgrease (zerk) fittings

33. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Snow Thrower Lubrication Points (Deere & Co.)

34. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Lubricating the Auger Shaft Lubricate grease fittings on auger shaft regularly –Two fittings –Wipe fittings clean and apply grease using grease gun –Wipe away excess grease If there are no grease fittings, disassemble parts and apply waterproof grease to auger shafts during reassembly

35. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Lubricating Auger Shaft Gearbox If filler plug is located at top of gearbox, drain the oil and add the correct amount If filler plug is at a level below the top of the gearbox, fill oil to the lower edge of the plug Refer to the manufacturer’s service information for the amount and type of oil to add

36. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Off Season Storage Add fuel stabilizer to fuel tank or drain fuel Remove spark plug and spray fogging oil into spark plug hole while slowly cranking engine Replace spark plug Clean snow thrower thoroughly with a clean cloth Store in normal position If storing outside, protect with a weather-resistant cover

37. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Starting after Storage 1.Remove and clean or replace spark plug 2.If fuel was drained, refill with fresh gasoline 3.Make sure cooling fins are clean 4.Check oil level and lubricate snow thrower 5.Replace worn or lose belts 6.Start engine and allow to warm up 7.Check condition of all controls

38. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Troubleshooting a Snow Thrower (MTD Products, Inc.)

39. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Review True or False? All heavy-duty snow throwers are powered by four-cycle engines. True

40. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Review What is the purpose of operator presence controls? Operator presence controls automatically stop the auger from rotating when the drive lever is released.

41. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Review Snow throwers with electric start systems also have _____ starters. recoil

42. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Review The height of the scraper bar above the surface is set by adjusting the _____. skid shoes

43. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Review True or False? A warm engine should be primed before attempting to restart it. False

44. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Review Why are shear bolts or pins used to connect the augers to their shafts? If something becomes lodged in the auger housing and stops the auger, the bolts or pins will shear to protect the auger and gearbox from damage.

45. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Review How is the auger shaft lubricated if there are no grease fittings on the shaft? The parts must be disassembled and waterproof grease must be applied to the auger shafts during reassembly.

46. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Glossary Augers –Helical-shaped steel shaft that rotates to pull snow into a snow thrower. Grease (zerk) fittings –Fittings to which a grease gun can be attached in order to lubricate an otherwise inaccessible part. Operator presence controls –A switch that stops the engine if the operator leaves the seat while the blades or PTO (power-take-off) is engaged.

47. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Glossary Rubber tracks –Components found on some heavy-duty snow throwers to provide exceptional traction on ice and snow. Scraper bar –Metal bar fastened along the bottom edge of a snow thrower’s auger housing intake. The scraper bar adds stiffness to the sheet metal housing and can be replaced when it becomes worn.

48. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Glossary Shear bolt –Bolt designed to protect a snow thrower’s auger and gearbox from serious damage by shearing if something becomes lodged in the auger housing and stops the auger. Single-stage snow throwers –Snow throwers that displace snow using only a horizontal auger that gathers and throws the snow through an adjustable deflector.

49. Permission granted to reproduce for educational use only.© Goodheart-Willcox Co., Inc. Glossary Skid shoes –Shoes located at the bottom edges of the snow thrower auger housing to absorb wear during operation and establish the height of the scraper bar above the surface. Two-stage snow throwers –Snow throwers in which the auger feeds the snow into a high-speed blower fan that ejects the snow out of the chute.