Generac Power Systems OHVI GSH 190, Service Manual

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SeCTIoN 13: TroubleSHooTING
ProbleM PoSSIble CAuSeS reMedY
1. engine will not start or starts a. Fuel tank is empty. a. Fill fuel tank.
with difficulty. b. Low oil level. b. Replenish oil as necessary.
c. Dirty air cleaner. c. Clean or replace
air cleaner element.
d. Obstructed fuel Line. d. Clean fuel line or replace.
e. Fuel tank cap vent hole is obstructed. e. Open cap vent hole.
f. Spark plug is fouled. f. Replace spark plug.
g. Incorrect spark plug. g. Replace with correct spark plug.
h. Loose or defective ignition wiring. h. Check wiring, repair or replace.
I. No ignition spark. I. Check ignition system, replace
defective part(s).
j. Incorrect valve clearance. j. Reset valve clearance.
k. Poor compression. k. Check for worn or scored cylinder.
2. engine knocks. a. Carbon in combustion chamber. a. Clean carbon from head
and piston.
b. Loose flywheel. b. Check flywheel key and keyway,
replace part(s) if necessary. Tighten
flywheel nut.
c. Worn cylinder. c. Replace crankcase.
d. Loose or worn connecting rod. d. Replace connecting rod. Check
crankpin diameter to see if
crankshaft is bad.
e. Incorrect valve clearance. e. Reset to correct clearance.
f. Engine is overloaded. f. Reduce excessive load.
3. engine misses under load. a. Incorrect spark plug. a. Install correct spark plug.
b. Spark plug is fouled. b. Replace spark plug.
c. Spark plug porcelain is cracked. c. Replace spark plug.
d. Incorrect spark plug gap. d. Regap the spark plug.
e. Incorrect valve clearance. e. Reset valve clearance.
f. Weak valve springs. f. Replace weak valve spring(s).
4. engine lacks power. a. Governor not set correctly. a. Adjust governor.
b. Incorrect spark plug b. Install correct spark plug.
c. Incorrect valve clearance. c. Reset valve clearance.
d. Worn piston rings. d. Replace piston rings.
e. Low oil level. e. Replenish oil to proper level.
f. Air cleaner is obstructed. f. Clean or replace air cleaner.
g. Valves or valve seats worn or burned. g. Grind valves and valve seats.
5. engine overheats.
a. Air flow is obstructed. a. Remove obstructions.
b. Cooling fins are clogged. b. Clean cooling fine.
c. Carbon buildup in combustion chamber. c. Remove cylinder head and
clean carbon.
d. Engine is overloaded. d. Reduce excessive loading.
e. Lack of lubrication e. Replenish oil to proper level.
6. engine vibrates excessively. a. Engine mounting bolts loose. a. Tighten mounting bolts.
b. Bent crankshaft. b. Replace crankshaft.
c. Problem in equipment c. Check equipment driven
connected to engine. by engine.
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