TM 5-3810-206-35
Replace all damaged mounting hardware. Replace all
(4) Install by reversing the procedures in steps
gaskets and seals.
(1) through (3) above.
b. Cleaning, Inspection, and Repair.
(1) Clean all parts and dry thoroughly be fore
3-49.
Vibration Damper (Engine Model 687C-18-ES)
inspection or reassembly.
a. Removal and Installation.
(2) Inspect ring, hub, and damper for breaks,
(1) Remove front cover (para 3-48).
cracks, or defective threaded surfaces.
Inspect
(2) Remove capscrews (22, fig. 3-53) and flat
mounting hardware for burs, stripped threads or other
washers (23), then remove damper (3) off of crankshaft
damage.
(3) Remove ring (1) from damper (3), then
(3) Repair by replacing all components that are
remove damper hub (2). Remove two dowels (24) from
damaged or defective.
ring (1).
Section XIV. CAMSHAFT
between camshaft and sleeve bearings for clearance of
3-50.
General
between 0.003 and 0.007 inch.
a. Engine Model 687C-18-ES.
The camshaft
assembly consists of a shaft and gear, with thrustwasher
Note. Use a narrow thickness gage
leaf, not more than 1/4 inch wide
The camshaft is driven by gear train at flywheel end of
when measuring this distance in
engine, and operates the exhaust valve mechanism.
order that accuracy may be assured.
b. Engine Model D333TA. The camshaft is located
Replace bearings in a set of seven, if
on the upper left side of cylinder block, and is driven by
one is worn more than 0.007 inch.
timing gear train at front end of engine. Camshaft is
positioned by a thrustwasher secured to cylinder block.
(3) Repair by replacing worn or defective
Cams operating inlet and exhaust valve mechanism are
components. Replace defective mounting hardware.
forged integrally with shaft. The camshaft and gear can
be removed as a unit, after timing gear cover has been
3-52.
Camshaft (Engine Model D333TA)
removed.
a. Remov al and Installation.
(1) Remove front cover (para 3-31).
3-51.
Camshaft (Engine Model 687C-18-ES)
(2) Remove valve operating mechanism (para
a. Removal and Installation.
(1) Remove valve operating mechanism (para
Caution: Use extreme care in
(2) Remove camshaft drive gear (para 3-30).
withdrawing camshaft from cylinder
(3) Remove thrustwasher (4, fig. 3-54) from
block so that cam lobes will not
crankcase.
damage sleeve bearings in block.
(4) Remove pin (3) from drive gear (2).
(5) Remove pin (7) from cramshaft (5).
(3) Remove nut (6, fig. 3-55) and retainer (5),
(6) Remove camshaft (5) from crankcase.
then pull gear (4) off camshaft (1).
(7) Remove
sleeve
bearings
(6)
from
(4) Remove bolts (7), lock (8) and washer (3)
crankcase.
from shaft (1). Remove key (2) from shaft (1).
(8) Install by reversing the procedures in steps
(1) through (6) above.
Note. If camshaft bearings are to be
b. Cleaning, Inspection, and Repair.
removed from block continue as
(1) Clean all parts and dry thoroughly before
follows:
inspection or installation.
(2) Use V blocks to support camshaft, with
(5)
Remove oil pan and plate (para 3-44).
paper strips soaked in oil to prevent scoring of journals.
(6)
Remove flywheel housing (para 3-41).
Attach a dial indicator at center journal and rotate
(7)
Press bearings out of cylinder block.
camshaft while reading the indicator. Reading must not
(8)
Install camshaft by reversing the procedures
be greater than 0.003 inch out of round. Measure each
in steps (1)
through (7) above.
camshaft journal with a micrometer for wear. Measure
3-65
