TM 5-3805-281-24-2
Camshaft and Timing Gear Train
CHECK CAMSHAFT END PLAY AND
MEASURE GEAR BACKLASH
NOTE: Camshaft end play must be measured before
removing timing gear cover, as thrust washer in
back side of timing gear cover limits camshaft end
play.
1. Remove injection pump drive gear cover (shown
removed).
2. Install magnetic base dial indicator on front face of
cylinder block and position dial indicator tip on front
face of camshaft gear, as shown. Set dial indicator to
zero.
3. Move camshaft gear back and forth and observe end
Measuring Camshaft End Play
play reading. Compare reading with specification given
below.
Camshaft--Specification
End Play ........................................................................ 0.013--0.500 mm
(0.0005--0.0200 in.) new
End Play ................................................... 0.65 mm (0.0260 in.) maximum
allowable
If end play is excessive, remove timing gear cover and
crankshaft and measure thickness of thrust washers.
4. Position indicator plunger tip against camshaft gear
tooth with a preload.
5. Measure backlash between camshaft drive gear and
crankshaft gear in three (3) different positions around
the camshaft gear. Compare readings with
specifications given below.
Camshaft Drive Gear Gear-to-Crankshaft Gear--Specification
Backlash ........................................................... 0.076 mm (0.003 in.) min.
Replace gear if backlash does not equal or exceed
specification.
RG,RG34710,1199
1923OCT971/1
