33
Problem: Engine noisy (Noise seems to come from secondary bevel gear and final driven shaft)
Condition
Remedy
1.
Drive - driven bevel gears
damaged - worn
2.
Backlash
incorrect
3.
Tooth contact
improper
4.
Bearing
damaged
5.
Gears
worn
6.
Splines
worn
1. Replace gears
2. Adjust backlash
3. Adjust contact
4. Replace bearing
5. Replace gears
6. Replace shaft(s)
Problem: Engine idles poorly
Condition
Remedy
1.
Valve clearance
incorrect
2.
Valve seating
poor
3.
Valve guides
defective
4.
Rocker arms - arm shaft
worn
5.
Magneto
defective
6.
CDI unit
defective
7.
Spark plug
fouled - gap incorrect
8.
Ignition coil
defective
9.
Float
out of adjustment
10.
Jets
obstructed
11.
Pilot screw setting
improper
1. Adjust clearance
2. Replace - service seats - valves
3. Replace guides
4. Replace arms - shafts
5. Replace stator coil
6. Replace CDI unit
7. Adjust gap - replace plug
8. Replace ignition coil
9. Adjust float height
10. Clean jets
11. Adjust pilot screw
Problem: Engine runs poorly at high speed
Condition
Remedy
1.
High RPM “cut out”
against RPM limiter
2.
Valve springs
weak
3.
Valve timing
incorrect
4.
Cams - rocker arms - tappets
worn
5.
Spark plug gap
incorrect
6.
Ignition coil
defective
7.
Fuel pump
defective
8.
Air cleaner element
obstructed
9.
Fuel hose
obstructed
10.
Float level
too low
1. Shift into higher gear - decrease speed
2. Replace springs
3. Time valves
4. Replace cams - arms - tappets
5. Adjust gap
6. Replace ignition oil
7. Replace fuel pump
8. Clean element
9. Clean or replace hose
10. Adjust float height
Problem: Exhaust smoke dirty or heavy
Condition
Remedy
1.
Engine oil
overfilled - contaminated
2.
Piston rings - cylinder
worn
3.
Valve guides
worn
4.
Cylinder wall
scored
5.
Valve stems
worn
6.
Stem seals
defective
1. Drain excess oil - replace oil
2. Replace - service rings - cylinder
3. Replace guides
4. Replace - service cylinder
5. Replace valves
6. Replace seals
Problem: Engine lacks power
Condition
Remedy
1.
Valve clearance
incorrect
2.
Valve springs
weak
3.
Valve timing
incorrect
4.
Piston ring(s) - cylinder
worn
5.
Valve seating
poor
6.
Spark plug
fouled
7.
Rocker arms - shafts
worn
8.
Spark plug gap
incorrect
9.
Carburetor jets
obstructed
10.
Cam chain
worn
11.
Air cleaner element
obstructed
12.
Engine oil
overfilled - contaminated
13.
Intake manifold
leaking air
14.
Float level
out of adjustment
1. Adjust clearance
2. Replace springs
3. Re-time valve gear
4. Replace - service rings - cylinder
5. Repair seats
6. Clean - replace plug
7. Replace arms - shafts
8. Adjust gap - replace plug
9. Clean jets
10. Replace cam chain
11. Clean element
12. Drain excess oil - change oil
13. Tighten - replace manifold
14. Adjust float height
Problem: Engine overheats
Condition
Remedy
1.
Carbon deposit (piston crown)
excessive
2.
Oil
low
3.
Octane
low - gasoline poor
4.
Oil pump
defective
5.
Oil circuit
obstructed
6.
Intake manifold
leaking air
7.
Fan
malfunctioning
8.
Fan relay
malfunctioning
9.
Gasoline level (in float chamber)
too low
1. Clean piston
2. Add oil
3. Drain - replace gasoline
4. Replace pump
5. Clean circuit
6. Tighten - replace manifold
7. Replace fan relay
8. Check fan fuse - replace fan
9. Adjust float height
