1.6.1 Connecting Rod
DETROIT DIESEL 53
CAUTION: Do not drive too hard on
the retainer or the bushing may be
moved inward and result in reduced
piston pin end clearance.
4. Slide the piston pin into the piston and the upper end
of the connecting rod. The piston pin will slip readily
into position without forcing it if the clearances are
5. Install the second piston pin retainer as outlined
6. After the piston pin retainers have been installed,
check for piston pin end clearance by cocking the
Fig. 8. - Reaming Piston Pin Bushings
connecting rod on the pin and shifting the pin in its
1. Clamp reaming fixture J 7608-4 in a vise.
7. One important function of the piston pin retainer is to
2. Slide sleeve J 7608-5 on the arbor of the fixture (V-
prevent the oil, which cools the underside of the piston
type engine connecting rod).
and lubricates the piston pin bushings, from reaching the
cylinder walls. Check the retainers for proper sealing as
3. Place the crankshaft end of the connecting rod on
the arbor of the fixture. Tighten the nuts on the 3/8" 24
Place the piston and connecting rod
assembly upside down on a bench.
4. Install the front guide bushing J 4971-6 in the fixture
(pin end out).
b. Pour clean fuel oil in the piston to a level,
above the piston pin bosses.
5. Install spacer J 7608-3 in the fixture.
6. Align the upper end of the connecting rod with the
hole in the reaming fixture.
7. Install the rear guide bushing J 1686-5 on the reamer
J 7608-21; then, slide the reamer and bushing into the
8. Turn the reamer in a clockwise direction only, when
reaming or withdrawing the reamer. For best results,
use only moderate pressure on the reamer.
9. Remove the reamer and the connecting rod from the
fixture, blow out the chips and measure the inside
diameter of the bushings. The inside diameter of the
bushings should be 1.3760" to 1.3765"
Assemble Connecting Rod to Piston
1. Apply clean engine oil to the piston pin and bushings.
Fig. 9. - Installing Piston Pin Retainer with Tool J 4895-
2. Rest the piston in the holding fixture (Fig. 9).
3. Place a new piston pin retainer in the piston; then,
place the crowned end of the installer J 4895-01 on the
retainer and strike the tool just hard enough to deflect
the retainer and seat it evenly.
1970 General Motors Corp.