1.4 Flywheel
DETROIT DIESEL 53
Inspection
Check the clutch contact face of the flywheel for scoring, overheating or cracks. If scored, the flywheel may be refaced.
However, do not remove more than .020" of metal from the flywheel. Maintain all of the radii when refacing the flywheel.
Although the flywheel seldom requires replacement, the flywheel ring gear may become worn due to normal usage or
damaged by improper use of the starting motor to the extent that it must be replaced. If replacement of the ring gear is
necessary, remove it as outlined below.
Remove Ring Gear
Note whether the ring gear teeth are chamfered. The replacement gear must be installed so that the chamfer on the teeth
faces the same direction with relationship to the flywheel as on the gear that is to be removed. Then remove the ring
gear as follows:
1. Support the flywheel, crankshaft side down, on a solid flat surface or a hardwood block which is slightly smaller than
the inside diameter of the ring gear.
2. Drive the ring gear off the flywheel with a suitable drift and hammer. Work around the circumference of the gear to
avoid binding the gear on the flywheel.
Install Ring Gear
1.
Support the flywheel, ring gear side up, on a solid flat surface.
2. Rest the ring gear on a flat metal surface and heat the gear uniformly with an acetylene torch, keeping the torch
moving around the gear to avoid hot spots.
CAUTION: Do not, under any circumstances, heat the gear over 400F.;
excessive heating may destroy the original heat treatment.
NOTE: Heat indicating "crayons", which are placed on the ring gear and melt at a
pre-determined temperature, may be obtained from most tool vendors. Use of
these "crayons" will ensure against overheating the gear.
3.
Use a pair of tongs to place the gear on the flywheel with the chamfer, if any, facing the same direction as
on the gear just removed.
4. Tap the gear in place against the shoulder on the flywheel. If the gear cannot be tapped into place readily, remove it
and apply additional heat, noting the above caution.
Install Flywheel
2.
If a clutch pilot bearing is used, install the bearing as outlined in Section 1.4.1.
3.
Install a new oil seal ring, if used.
4. Attach flywheel lifting tool J 6361-01 to the flywheel with two 3/8"-16 bolts. Then, with the use of a chain hoist,
position the flywheel in the flywheel housing or clutch housing.
5. Apply a small quantity of International Compound No. 2, or equivalent, to the threads and contact areas of the six
attaching bolts.
6. While holding the flywheel in place by hand, remove the flywheel lifting tool and install the flywheel attaching bolts
and scuff plate. Tighten the 1/2 "-20 bolts on all engines to 110-120 lb-ft torque.
NOTE: Tighten the flywheel bolts accurately, but do not exceed the specified
torque. International Compound No. 2 must never be used between two surfaces
where maximum friction is desired, such as between the crankshaft and the
flywheel.
7. Mount a dial indicator on the flywheel housing or clutch housing and check the runout of the flywheel at the clutch
contact face. Maximum allowable runout is .001" total indicator reading per inch of radius (the radius is measured from
the center of the flywheel to the outer edge of the clutch contact face of the flywheel).
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