Starting System Troubleshooting - Cessna 177 SERIES Service Manual

armature turns the reduction gear, the Bendix drive
pinion meshes with the crankshaft ring gear assembly iCAUTION_
by inertia and action of the screw threads within the
Bendix sleeve. A detent pin engages in a notch in the Never operate the starter motor more than
screw threads which prevents demeshing if the engine 12 seconds at a time. Allow starter motor
fails to start when the starting circuit is de-energized. to cool between cranking periods to avoid
When the engine reaches a predetermined speed, cen- overheating. Longer cranking periods with-
trifugal action forces the detent pin out of the notch in out cooling time will shorten the life of the
the screw shaft and allows the pinion to demesh from starter motor.
the ring gear.
11-75. TROUBLE SHOOTING.
TROUBLE PROBABLE CAUSE REMEDY
STARTER WILL NOT OPERATE. Defective master switch or Check continuity of master
circuit. switch and circuit.
Install new switch or wires.
Defective starter switch or Check continuity of switch
switch circuit. and circuit.
Install new switch or wires.
Defective starter motor. Check voltage to starter.
If voltage is present.
Remove, repair or install
new starter motor.
STARTER MOTOR RUNS, BUT Defective Bendix drive. Remove starter and inspect
DOES NOT TURN CRANK- Bendix drive.
SHAFT.
Replace defective parts.
Damaged starter pinion Inspect starter pinion gear
gear or ring gear. and ring gear. Replace
defective parts.
STARTER MOTOR DRAGS. Low battery. Check battery.
Charge or install new battery.
Starter switch or relay contacts Install serviceable unit.
burned or dirty.
Defective starter motor Inspect cable.
power cable. Install new cable.
Loose or dirty connections. Inspect connections.
Remove, clean and tighten all
terminal connections.
Defective starter motor. Check starter motor brushes,
brush spring tension, thrown
solder on brush cover. Repair
or install new starter motor.
Dirty or worn commutator. Inspect commutator.
Clean and turn commutator.
STARTER EXCESSIVELY Worn starter pinion gear or Inspect starter pinion gear and
NOISY. broken teeth on ring gear. ring gear. Replace defective
parts.
Change 2 11-29