Yamaha EF1000iS, Service Manual

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6-4
ENGINE
TRBL
ENGINE SPEED DOES NOT INCREASE
Check if the electric equipment consumes too much
wattage for this generator.
GOOD TOO MUCH
Use a generator with a larger capacity.
Check air filter element for dirt.
GOOD NO GOOD Clean.
Check spark plug for dirt and check spark plug gap.
GOOD NO GOOD Clean or adjust.
Check valve clearance.
GOOD NO GOOD
Adjust.
Check if main passages such as, the main jet, in the
carburetor are clogged.
GOOD NO GOOD
Disassemble or clean.
Check for air suction due to a damaged throttle shaft
seal, carburetor joint, or gasket.
GOOD NO GOOD
Disassemble or replace.
Check compression using compression gauge.
GOOD
TOO HIGH
TOO LOW
Decarbonize combustion chamber if
there are carbon deposits.
Check valve face and valve seat for wear.
GOOD NO GOOD
Resurface or replace.
Check if the marks on the crankshaft and camshaft
are aligned.
GOOD NO GOOD
Correct.
Check if there is seizure or wear on piston, piston ring,
or cylinder.
GOOD
SEIZURE OR
WEAR
Rebore or replace.
Check the condition of the throttle control system.
Refer to “THROTTLE CONTROL SYSTEM”.
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