FAA Advisory Circular 43.13-1B
Acceptable Methods, Techniques, and Practices
Aircraft Inspection and Repair
AC 43.13-1B | 8. Engines, Fuel, Exhaust, and Propellers | 1. Engines | 8-2. Special Inspection
AC 43.13-1B
9/8/98
the mounting hardware, isolation mounts, and
bushings. The aircraft’s firewall must also be
checked for distortion, cracks, and elongated
bolt holes. The damaged propeller must be
sent to an FAA-certificated repair station for
complete NDI and repair.
(4) Engine accessories such as: magne-
tos, starters, fuel pumps, turbochargers, alter-
nators, or generators must be inspected in ac-
cordance with the manufacturer’s maintenance
manual on sudden stoppage or overhaul proce-
dures to determine the product’s airworthiness.
c. Reciprocating Engine (Direct Drive).
Preliminary inspection before tear down.
(1) Remove the engine cowling and ex-
amine the engine for visible external damage
and audible internal damage.
(2) Rotate the propeller shaft to deter-
mine any evidence of abnormal grinding or
rubbing sounds.
particular attention to the propeller thrust-
bearing area of the nose case section.
(8) Inspect cylinders and cylinder hold-
down area for cracks and oil leaks. Thor-
oughly investigate any indication of cracks, oil
leaks, or other damage.
d. Internal Inspection Requirements.
(1) On engines equipped with crank-
shaft vibration dampers, remove and inspect
the cylinders, and inspect the crankshaft damp-
ers in accordance with the engine manufac-
turer’s inspection and overhaul manual. When
engine design permits, remove the damper
pins, and examine the pins and damper liners
for signs of nicks or brinelling.
(2) After removing the engine-driven
accessories, remove the accessory drive case
and examine the accessory and supercharger
drive gear train, couplings, and drive case for
evidence of damage.
(3) With the propeller removed, inspect
the crankshaft flange or splines for signs of
twisting, cracks, or other deformation. Re-
move the thrust-bearing nut and seal and thor-
oughly inspect the threaded area of the shaft
for evidence of cracks.
(a) Check for cracks in the case in
the area of accessory mount pads and gear
shaft bosses.
(b) Check the gear train for signs of
cracked, broken, or brinelled teeth.
(4) Rotate the shaft slowly in 90-degree
increments while using a dial indicator or an
equivalent instrument to check the concentric-
ity of the shaft.
(5) Remove the oil sump drain plug and
check for metal chips and foreign material.
(6) Remove the oil screens and inspect
for metal particles and contamination.
(7) Visually inspect engine case exterior
for signs of oil leaks and cracks. Give
(c) Check the accessory drive shaft
couplings for twisted splines, misalignment,
and run-out.
(d) Check connecting rods for cracks
and straightness.
e. Reciprocating Engine (Gear-Drive).
Inspect the engine, propeller, (refer to section 4
on propeller inspection), and components as
described in the preceding paragraphs.
(1) Remove the propeller reduction gear
housing and inspect for:
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