DETROIT DIESEL 53
Connecting Rod 1.6.1
to .0019" with a new piston pin. A new piston pin has a diameter of 1.3746" to 1.3750".
Assemble Connecting Rod to Piston
Apply clean engine oil to the piston pin and bushings. Refer to Fig. 2 and assemble the connecting rod to the piston as
follows:
1. Place the piston in the holding fixture (Fig. 9).
2. Place a new piston pin retainer in position. Then place the crowned end of installer J 23762 against the retainer and
strike the tool just hard enough to deflect. the retainer and seat it evenly in the piston.
CAUTION: Do not drive the retainer in too far or the piston bushing may be moved
inward and result in reduced piston pin end clearance.
3. Place the upper end of the connecting rod between the piston pin bosses and in line with the piston pin holes. Then
slide the piston pin in place. If the piston pin-to-bushing clearances are within the specified limits, the pin will slip into
place without use of force.
4. Install the second piston pin retainer as outlined in Steps I and 2.
5. After the piston pin retainers have been installed, check for piston pin end clearance by cocking the connecting rod
and shifting the pin in its bushings.
6. One important function of the piston pin retainer is to prevent the oil, which cools the underside of the piston and
lubricates the piston pin bushings, from reaching the cylinder walls. Check the retainers for proper sealing as follows:
a. Place the piston and connecting rod assembly upside down on a bench.
b. Pour clean fuel oil in the piston to a level above the piston pin bosses.
c. Dry the external surfaces of the piston in the area around the retainers and allow the fuel oil to set for about
fifteen minutes.
d. Check for seepage of fuel oil around the retainers. If the fuel oil leaks around the retainers, install new retainers.
In extreme cases, it may be necessary to replace the piston.
e. After the leakage test is completed, empty the fuel oil from the piston, dry the parts with compressed air and
lubricate the piston pin with clean engine oil.
7. Install the piston rings on the piston as outlined in Section 1.6.
8. Install the piston and connecting rod assembly in the engine as outlined in Section 1.6.3.
April, 1974 Sec. 1.6.1 Page 5
