1.6.2 Connecting Rod Bearings
DETROIT DIESEL 53
2. Install the upper bearing shell the one with the short
Bearing shells which are .002" undersize are available
groove and oil hole at each parting line in the
to compensate for slight journal wear in those cases
connecting rod. Be sure the tang on the shell fits in the
where it is unnecessary to regrind the crankshaft.
groove in the rod.
NOTE: Bearing shells are NOT
If there is a visible difference in the color of new upper
reworkable from one undersize to
and lower bearing shells, it is due to a change in the
another under any circumstances.
manufacturing process and they should not be rejected
on the basis of the dissimilar appearance.
The following table gives the minimum bearing shell
thickness for used standard and various undersize
3. Pull the piston and rod assembly down until the
bearings, and the crankshaft connecting rod journal
upper rod bearing seats firmly on the crankshaft journal.
diameters corresponding to each bearing size.
4. Place the lower bearing shell the one with the
continuous oil groove in the bearing cap, with the tang
of the shell in the groove of the cap, and lubricate it with
clean engine oil.
5. Note the identifying marks on the cap and the rod
and assemble the cap to the rod. Tighten the nuts on
the 3/8" -24 bolts
to 40-45 lb.-ft
6. Install the lubricating oil pump inlet tube assembly.
Replace the inlet tube seal ring or elbow gasket if
hardened or broken.
7. Install the oil pan.
8. Refer to the Lubricating Oil Specifications in Section
* Dimension' of Reground Crankshaft
13.3 and refill the crankcase to the proper level on the
Install Connecting Rod Bearing Shells
(Connecting Rod, Piston and Liner in Place)
9. If new bearings were installed, operate the engine on
the run-in schedule as outlined in Section 13.2.1.
1. Rotate the crankshaft until the connecting rod journal
is at the bottom of its travel, wipe the journal clean and
1970 General Motors Corp.