Fuels and Lubricants for Small Engines

1. Fuels and Lubricants for Small Engines UT Extension

2. Jim Wills • Biosystems Engineering and Environmental Science Department • Extension • University of Tennessee UT Extension

3. Two Main Types of Small Engines on Lawn and Garden Equipment • Four-Stroke Cycle • Two-Stroke Cycle UT Extension

4. Cooling System • Most engines on lawn and garden equipment are air cooled • Fan on flywheel circulates air over engine for cooling while engine is running • Water cooled engines have radiator and liquid coolant circulating in water jacket around engine UT Extension

5. Flywheel/Fan UT Extension

6. Four-Stroke Engines • Four strokes* of the engine for one power cycle • Stroke 1 – Intake • Stroke 2 – Compression • Stroke 3 – Power • Stroke 4 – Exhaust * A stroke is one up or down movement of the piston in the cylinder UT Extension

7. Four-Stroke Operation UT Extension

8. Typical Four Stroke Lawn and Garden Equipment • Push-Type Lawn Mowers • Lawn Tractors • Garden Tractors • Pressure Washers • Chippers/Shreaders • Garden Tillers UT Extension

9. Two Stroke Operation UT Extension

10. Typical Two-Stroke Equipment • Chainsaws • Weed Trimmers • Leaf Blowers • Hedge Clippers • Air Compressors • Small Garden Tillers • Some push type lawnmowers UT Extension

11. Four-Stroke Engine Characteristics • Separate fuel tank and oil reservoir • Heavier/larger than same HP two-cycle • Cannot be tilted much to side • Longer engine life • Larger HP uses UT Extension

12. Two-Stroke Engine Characteristics • Fuel and oil are mixed in fuel tank • No separate reservoir for oil* • Can be operated on side and upside down • Lighter/smaller for given HP • Shorter overall engine life • Usually more noise and smoke * Some boat motors and motorcycles havea reservoir UT Extension

13. Main Causes of PrematureSmall Engine Failure(Short Engine Life) UT Extension

14. Dirt! • 60% to 70% of all failures are caused by dirt* getting into engine *Dust, insects, bits of grass, etc. UT Extension

15. Service air filter on a regular basis (usually once a season) • Service more often under dusty or adverse conditions UT Extension

16. For every gallon of gasoline used, the air filter must clean 10,000 to 11,000 gallons of air UT Extension

17. Air Filter – Paper Type UT Extension

18. Carburetor UT Extension

19. Failure to use proper oil* * Viscosity (thick or thin) * API Classification (SJ, SL, Etc.) UT Extension

20. Failure to change oil on a regular schedule • Mileage • Hours of use • Time of use (weeks, months, etc.) UT Extension

21. Failure to maintain proper oil level in crankcase • Check dip stick • Check oil level plug UT Extension

22. Checking Oil Level UT Extension

23. Failure to use clean, fresh fuel • Dirty fuel tank • Dirty fuel can • Dirty funnel • Trash/dirt around fuel cap UT Extension

24. Install a fuel filter on fuel line if not factory equipped UT Extension

25. Fuel Filter UT Extension

26. Use a suitable fuel container to prevent fuel contamination and insure safety • Metal cans will eventually rust inside • Plastic containers will not rust • Use a funnel with mesh filter UT Extension

27. Can Good Plastic Fuel UT Extension

28. Failure to use proper fuel • Unleaded fuel is cleaner burning • Choose proper fuel octane level • Do not use fuel containing alcohol • Use lead substitutes if 1974 or older UT Extension

29. Operating tips to extend engine life • Let engine idle for two minutes before stopping • Never stop under load • Avoid stalls and sudden impacts UT Extension

30. Avoid Impacts UT Extension

31. Flywheel Keyway UT Extension

32. SAFETY!!! • Use approved fuel containers • Never fuel a hot engine • Stop engine before making repairs or adjustments UT Extension

33. Motor Oils UT Extension

34. Castrol Brand Oil UT Extension

35. Functions of Motor Oil • Lubricate moving parts • Seal around gaskets, seals, piston rings • Clean contaminates from engine parts • Remove excess heat from engine UT Extension

36. Oil container has information on oil quality and viscosity UT Extension

37. API (American Petroleum Institute) circle contains API Service Classification and Viscosity UT Extension

38. API Circle UT Extension

39. VISCOSITY • Is the oil thick or thin? • Affected by temperature • Affected by shear of oil molecules in lubrication process • All oils are tested at same temperatures to establish viscosity rating UT Extension

40. Viscosity Values • SAE 0W, 5W, 10W, 15W, 20W • SAE 30, 40, 50 • SAE 10W-30, 5W-30, 15W-50, 10W-40, etc. • “W” means suitable for wintertime use (cold temperatures) • “SAE”- Society of Automotive Engineers UT Extension

41. API Service Classifications • “S” - for gasoline engines (S- Spark ignition) • “C” - for diesel engines (C- Compression ignition) UT Extension

42. Gasoline Classes • SA, SB, SC, SD, SE, SF, SG, SH, SJ, SL • SA is lowest quality • SL is highest quality UT Extension

43. Diesel Classes • CA, CB, CC, CD, CE, CF, CG, CH • CA is lowest quality • CH is highest quality UT Extension

44. Petroleum Based Oils • Base stock of about 85% oil by volume • Additives of about 15% by volume • Additives include detergent, anti-oxidation, anti-corrosion, extreme heat, extreme pressure, anti-rust, etc. UT Extension

45. Value of Oil Additives? • Slick 50, T-Plus, STP, Motor Honey, etc. • Usually not worth the price !!! UT Extension

46. T-Plus Additive UT Extension

47. Why Change Motor Oil? • Replace additives • Remove contaminants ( water, acid, carbon, etc. UT Extension

48. When to Change Motor Oil? • At recommended mileage (3,000 on cars, trucks, campers, etc.) • At 50 hours on small engines • More often under severe conditions (pulling heavy loads, steep climbing, etc.) • Change when oil is hot, not cold UT Extension

49. Changing Brands of Oil • You do not have to use the same brand of oil forever in a given engine • To change brands, drain old brand and replace with new brand – change oil filter at same time • Use same viscosity UT Extension

50. Oil for Your Small Engines • SAE 30* • SAE 10W-30 • Synthetic oil * Above 40 degrees F UT Extension