Generac Power Systems OHVI GSH 190, Руководство по обслуживанию

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SeCTIoN 13: TroubleSHooTING
ProbleM SolvING
INTRODUCTION:
Problems that affect engine operation may be classified as
one of, or a combination of two or more of the following:
• Engine will not start.
• Engine starts with difficulty.
• Engine lacks power.
• Engine vibrates.
• Engine overheats.
• Engine burns oil.
In many cases, the cause of a problem will be readily appar-
ent. If this is not the case, check the fuel system, as well as
the ignition system and engine compression. Such a check can
be performed quickly and is the best method of finding the
cause of a failure. In addition, such a check may provide early
detection of future failures.
CHECK FUEL SYSTEM:
Make sure the fuel tank has been properly filled with the
correct fuel. If the engine is equipped with a fuel shutoff valve,
make sure the valve is open. Make sure fuel is flowing through
the fuel line and to the carburetor. Adjust the carburetor as
needed. Make sure the choke closes all the way. If engine still
will not start, remove and inspect the spark plug.
If the plug is WET, look for the following:
. Overchoking.
2. Dirty air cleaner.
. Excessively rich fuel-air mixture.
. Water in the fuel.
5. Fuel leaking past the carburetor float needle.
If the plug is DRY, look for the following:
. Carburetor mounting gasket leaks.
2. Dirt or gum in carburetor or fuel line.
. Carburetor float needle stuck closed.
. Inoperative fuel pump (if so equipped).
5. Clogged fuel filter (if so equipped).
CHECK IGNITION SYSTEM:
See "Testing the Ignition System" in Section 8.
CHECK COMPRESSION:
To check engine compression, remove the spark plug. Insert
an automotive type compression gauge into the spark plug
hole. Crank the engine until there is no further increase in
pressure. The highest reading obtained is the engine compres-
sion pressure.
If compression is poor, look for one or more of the follow-
ing causes:
• Loose cylinder head bolts.
• Failed cylinder head gasket.
• Burned valves or valve seats.
• Insufficient valve clearance.
• Warped cylinder head.
• Warped valve stem.
• Worn or broken piston ring(s).
• Worn or damaged cylinder bore.
• Broken connecting rod.
• Worn valve seats or valves.
• Worn valve guides.
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