10.
See the applicable Lycoming Parts Catalog for the particular engine model for correct propeller flange bushings and install new plated service bushings in the flange. Chill the bushings by refrigeration and install with Lycoming Service Tool No. ST-115.
11.
Support crankshaft in vee-blocks at the end journals and measure run-out at refinished area. Total indicated run-out must not exceed 0.002 inch.
12.
Examine crankshaft by magnetic particle method.
7-43. Crankshaft Counterweight Bushing Replacement (Where Applicable). Wear or damage to the crankshaft counterweight bushing located in the counterweight lobes
is almost impossible to detect by normal inspection pro-cedures. Because of the possible damage to the counterweight and/or the crankshaft from wear or
damage counterweight bushing, it is mandatory that the bushing be replaced at overhaul. The procedure for removal and replacement of the crankshaft counterweightbushings is as follows:
COUNTERWEIGHT COUNTERWEIGHT
EAR ROLLERBUSHING ON CRANKSHAFT
4 3 2 1
COUNTERWEIGHT PULLER
BUSHING
Figure 7-9. Removal of Crankshaft Counterweight Bushing
Section7 OVERHAUL MANUAL
LYCOMING
Crankcase,Crankshaft
and ReciprocatingParts
1. (See figure 7-9). Thread the bolt of the counte rweight
bushing puller P/N 64872 through the puller pla te (2) so
that the recess of the plate will be next to the cra nkshaft
lobe when bolt is inserted through the crankshaft
counterweight bushing. Install the small puller 1bushing
(3) over end of bolt and install nut (4)on bolt. As the nut
is tightened on the bolt, the counterweight bushhing will
be pushed out of its recess in the cra nkshaft
counterweight mounting lobe and into the recessss of the
puller plate.
2. Measure the inside diameter of the hole in the
crankshaft lobe that the bushing was removed from. If
the hole in the lobe measures .9369 to .9377 inch no
reaming of the hole is necessary and a standardard size
bushing can be installed. If the hole measureses more
than .9377 inch, the next oversize bushing mustst be in-
stalled and the hole must be reamed gly. See
accordingly.
Table 7-2 for the proper reamer.
TABLE 7-2
Hole Size Reamer No.
.9369/.9377 None
.9420/.9425 64874 .9445/.9450 ST-210 .9470/.9475 64875 .9495/.9500 ST-211 .9520/.9525 64876
3.
Determine the oversize reamer needed and asssemble
the reaming fixture (ST-280) over the crankshhaft ear.
Select the two opening in the fixture to line up with
the
bushing holes and install the plugs provided to line up
the holes in the fixture with the holes in the cra nkshaft
ears. Secure the fixture by tightening the set screw.
Assemble the reamer in a suitable handle and prooceed to
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