Yanmar 1GM User Manual page 100

94
6. Remove the bearing retaining screw (Fig ure 83), then
withdraw the camshaft.
7. Remove the valve lifters and mark them so they may
be reinstalled in thei r original locations.
8. Check the rear bearing journal and lobes for signs of
wear or sconng.
NOTE
If
precision measuring equipment is not
available, have a dealership or machine
shop perform Step 9.
9. Measure the rear camshaft journal diameter and lobes
(Figu re 84) and compare the measurement 10the specifi-
cation in Ta ble I. Replace the camshaft if the journal or
lobes do not meet specifications.
10. Measure the stem diameter of the valve lifters and
compare the measurement to the specificat ion in Table I .
Measure the lifter bores in the cy linder block. Calculate
the lifter clearance and compare it with the spec ification
in Table L Replace the valve lifters if they do not meet
specifications. Replace the valve lifter if the lifter face is
scored, galled, excessively worn or otherwise damaged.
CHAPTER FIVE
Fuel transfer
pu mp lo be
Intake valve
lo be
Exhau st
va lve
lob e
11. Replace the ball bearing if it is damaged or feels
rough during rotation.
12. Installation is the reverse of removal . Note the fol-
lowing:
a. If installing a new camshaft, coat the camshaft lobes
with camshaft break-in lubricant. Ifrcinstalling tbc
original camshaft, apply heavy oil to the camshaft
lobes .
b. Lubricate the camshaft bearing journal with heavy
eng ine oil before reinstallation.
c. Lightly tap the end of the camshaft to seat the ball
bearing in the eng ine. Rotate the camshaft 10be sure
it rotates freely.
d. Align the timing marks (Figure 78) on the camshaft
and crankshaft gears when installing the camshaft
gear.
c. Install the fuel injection cam so the side marked
with a zero is out (F igure 85) .
f. Check gear backlash by installing a dial indicator as
shown in Figure 79 or by rotating the gear teeth
with soft solder between the gear teeth. Compa re
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