Cessna 177 SERIES Service Manual page 153

11-13. TROUBLE SHOOTING (Cont).
TROUBLE
PROBABLE CAUSE
REMEDY
ENGINE STARTS BUT
Idle stop screw or idle mixture
Refer to paragraph 11-49.
DIES, OR WILL NOT
incorrectly adjusted.
IDLE.
Carburetor idling jet plugged.
Clean carburetor and fuel strainer.
Refer to paragraph 11-48.
Spark plugs fouled or improperly
Remove, clean and regap plugs.
gapped. Replace if defective.
Water in fuel system.
Open fuel strainer drain and check
for water. If water is present,
drain fuel tank sumps, lines,
strainer and carburetor.
Defective ignition system.
Refer to paragraph 11-63.
Vaporized fuel.
(Most likely Refer to paragraph 11-85.
to occur in hot weather with
a hot engine.)
Induction air leaks. Check visually.
Correct the
cause of leaks.
Manual primer leaking.
Disconnect primer outlet line.
If fuel leaks through primer,
repair or replace primer.
Leaking float valve or float
Perform an idle mixture check.
level set too high. -
Attempt to remove any rich
indication with the idle mixture
adjustment. If the rich indica-
tion cannot be removed, the
float valve is leaking or the
float level is set too high.
Re-
place defective parts, reset
float level.
Defective carburetor. If engine will start when primed
but stops when priming is dis-
continued, with mixture control
in full RICH position, the carbu-
retor is defective.
Repair or
replace carburetor.
Defective engine.
Check compression. Listen for
unusual engine noises.
Engine
repair is required.
ENGINE RUNS ROUGHLY Restriction in aircraft fuel
Refer to Section 12.
OR WILL NOT ACCELERATE
system.
PROPERLY.
Worn or improperly rigged
Check visually. Replace worn
throttle or mixture control.
Linkage. Rig properly.
Spark plugs fouled or im-
Remove, clean and regap plugs.
properly gapped. Replace if defective.
Defective ignition system.
Refer to paragraph 11-63.
Change 5
11-7