Non-Overhaul Removal and Replacement
Teledyne Continental Motors, Inc.
TM
10-42
IOF-240 Series Engine Maintenance Manual
29 November 2006
10-8.
Crankcase Repair
Cracks occur on the cast aluminum crankcases for various reasons (e.g., improper
crankcase assembly or maintenance).
WARNING
Do not allow a cracked crankcase that exhibits the damage
described below to remain in service. Engine failure is
imminent if the conditions persist.
CAUTION: All cracks require attention, regardless of size or
location. Do not ignore crankcase cracks.
10-8.1. Crankcase Repair and Replacement Criteria
The following criteria should be applied for crankcases repair or replacement:
Any crack in the cylinder deck (white/non-shaded - critical areas) requires immediate
crankcase replacement. Refer to the affected white areas in Figure 10-24. Any crack 1-
inch (2.54 cm) or more in length in the shaded (non-critical) locations in Figure 10-24
requires repair or replacement of the crankcase.
Scribe cracks smaller than 1 inch in the non-critical areas at the extremities for further
growth progression monitoring. Any crack with seeping oil must be repaired or replaced
immediately. At 25-hour inspection intervals, inspect the progression of any previously
identified crack located in the shaded locations of Figure 10-24 that is less than 1 inch in
length. If the crack progresses to 1 inch or more in length in the shaded locations of
Figure 10-24, repair or replace the crankcase.
10-8.1.1. Crankcase Weld Repairs
WARNING
An FAA-approved repair facility is the only facility authorized
to perform a crankcase weld repair.
No weld repairs are to be done on the critical (non-shaded)
areas of the crankcase (Figure 10-24) or the bearing support
structures.
