DETROIT DIESEL 53
Crankshaft 1.3
Fig. 8. Standard Dimensions at Rear Main
Bearing Thrust Washers and V-Type
Engines
installed, ALL new main and connecting rod (upper and
lower) bearing shells and new thrust washers must also
be installed.
Fig. 1. - Checking Crankshaft End Play
1. Assemble the crankshaft timing gear (Section 1.7.5)
5. Install the lower bearing shells (no oil grooves) in the
and the oil pump drive gear (Section 4.1) on the
bearing caps. If the old bearing shells are to be used
crankshaft.
again, install them in the same bearing caps from which
they were removed. Lubricate the bolt threads and bolt
2. Install the upper grooved bearing shells in the block.
head contact surfaces with a small quantity of
If the old bearing shells are to be used again, install
International Compound No. 2, or equivalent. Install
them in the same locations from which they were
the bearing caps and draw the bolts up snug. Then, rap
removed.
the caps sharply with a soft hammer to seat them
properly.
3. Apply clean engine oil to all crankshaft journals and
install the crankshaft in place so that the timing marks
6. Draw the bearing cap bolts uniformly tight, starting
on the crankshaft timing gear and the idler gear match).
with the center cap and working alternately toward both
Refer to Section 1.7.1 for the correct method of timing
ends of the block, to 120-130 lb-ft torque. On a V-type
the gear train.
engine, tighten the stabilizer to cylinder block bolts to
46-50 Ib-ft torque. Rotate the crankshaft to make sure
4. Install the upper halves of the crankshaft thrust
that it rotates freely.
washers on each side of the rear main bearing support
and the doweled lower halves on each side of the rear
main bearing cap. The grooved side of the thrust
properly, the crankshaft will turn freely with
washers must face toward the crankshaft thrust
all of the main bearing cap bolts drawn to
surfaces.
the specified torque.
NOTE: If the crankshaft thrust surfaces were reground,
7. Check the crankshaft end play by moving the
it may be necessary to install oversize thrust washers on
crankshaft toward the gage (Fig. 9') with a pry bar.
one or both sides of the rear main journal. Refer to Fig.
Keep a constant pressure on the pry bar and set the dial
8 and Table 2.
indicator to zero. Then, remove and insert the pry bar
on the other side of the bearing cap. Force the
crankshaft in the opposite direction and note the amount
of end play on the dial. The end play should be .004" to
.011" with new parts or a maximum of .018" with used
parts. Insufficient end play can be the
1972 General Motors Corp.
February, 1972
SEC. 1.3 Page 7
