Tecumseh HH100 Handbook page 65

Cause
Governor not properly adjusted.
Carburetor not properly adjusted.
Intermittent spark at spark plug.
G. ENGINE VIBRATES EXCESSIVELY
Engine not securely mounted.
Bent crankshaft.
Associated equipment out of balance.
Counterbalance counterweights not properly aligned. Check.
H. ENGINE USED EXCESSIVE AMOUNT OF OIL.
Engine speed too fast.
Oil level too high.
Oil filler cap loose or gasket damaged causing
spillage out of breather.
Breather mechanism damaged or dirty causing
leakage.
Gaskets or "O" rings damaged or gasket or "O" ring
surfaces nicked causing oil to leak out.
Valve guides worn.
Cylinder wall worn or glazed allowing oil to pass
rings into combustion chamber.
Piston rings and grooves worn excessively.
Piston fit too loose.
Piston oil control ring return holes clogged.
Oil passages obstructed.
I. OIL SEAL LEAKS
Seal hardened or worn.
Crankshaft seal contact surface is slightly
scratched causing seal to wear excessively.
Crankshaft bearing under seal is worn excessively Check crankshaft bearings for wear and replace if
causing crankshaft to move.
Seal outside seat (oil seal bore) in cylinder or
side cover is damaged allowing oil to seep
around outer edge of seal.
New seal installed without correct seal driver
and not seating squarely in cavity.
Remedy
Adjust governor.
Adjust carburetor.
Disconnect ignition cut-off wire at the engine. Crank
engine. If spark, check ignition switch, safety switch
and interlock switch. If no spark, check magneto.
Check wires for poor connections cuts or breaks.
Tighten loose mounting bolts.
Replace crankshaft.
Check associated equipment.
Using tachometer adjust engine RPM to specification.
Check level turn dipstick cap tightly into receptacle for
accurate level reading.
Replace ring gasket under cap and tighten cap securely.
Replace breather assembly.
Install new gaskets or "O" rings.
Ream valve guide oversize and install 1/32'' (.787 mm)
oversize valve.
Deglaze cylinder as necessary.
Reinstall new rings and check land clearance and correct
as necessary.
Measure and replace as necessary.
Remove oil control ring and clean return holes.
Clean out all oil passages.
Replace seal.
Crankshaft seal rubbing surface must be smoothed
before installing new seal. Use a fine crocus cloth.
Care must be taken when removing seals.
necessary.
Visually check seal receptacle (oil seal bore) for
damage. Replace P.T.O. cylinder cover or small cylinder
cover on the magneto end, if necessary.
Replace with new seal using proper tools and methods.
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