ARMY TM 9-2815-259-24
AIR FORCE TO 38G1-125-2
MARINE CORPS 09249A/09246A-24
Table 5-8. Connecting Rod Piston Pin Bushing Specifications.
Connecting Rod Piston Pin Bushing ID
1.6260 - 1.6290 in. (41.300 - 41.376 mm)
Piston Pin-to-Bushing Oil Clearance
0.0007 - 0.0040 in. (0.020 - 0.102 mm)
If necessary, replace connecting rod piston pin bushing in straight pin-end rod as follows:
Oil holes must be aligned. If holes are not aligned, remove and discard
bushing. Install a new bushing. DO NOT attempt to reuse the bushing.
Install bushing in rod.
Use driver for 1.6 in. (41 mm) pin to install bushing.
Press bushing into rod bore until edge of bushing is flush or just slightly below
machined surface on face of rod.
Remove rod from press.
inner diameter of bushing must be precision bored to proper size. Pin-to-Bushing oil
clearance should be 0.0007 - 0.0022 in. (0.020 - 0.056 mm) and wear limit should be
0.0040 in. (0.102 mm).
(m) Calculate piston pin-to-bushing oil clearance by subtracting piston pin (9) outer diameter
from connecting rod piston pin bushing (10) inner diameter. Compare piston pin-to-bushing
oil clearance with specifications given in Table 5-8. Replace connecting rod piston pin
bushing, refer to step l, or piston pin if out of specifications.
Insert piston pin (9) from either side of connecting rod piston pin bushing (10). Replace
connecting rod piston pin bushing, refer to step l, if piston pin is free on one end but tight on
the other, or if piston pin enters freely from both sides, but is tight in the center.
Measure rod center-to-center bore as follows;
Measure rod center-to-center bores (with bushings removed). Bearing bore-to-pin
bushing (center-to-center) length A should be 7.990 - 7.994 in. (202.95 - 203.05
mm). Refer to Figure 5-77.
Replace rod if not within specifications.