Yanmar 3TNV88F, Руководство по обслуживанию

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ENGINE
6-36
3TNV88F Service Manual
Crankshaft and Camshaft Components
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Removal of camshaft
1. Before removing the camshaft, check the
camshaft end play.
• Method A: Install a dial indicator
(Figure 6-48, (1)) on the cylinder block. Move
the camshaft (Figure 6-48, (2)) back and forth
to measure the end play. Record the
measurement.
See Camshaft on page 6-6 for
the service limit.
Figure 6-48
• Method B: Use a feeler gauge to measure the
clearance between the thrust plate
(Figure 6-49, (1)) and front camshaft bearing
(Figure 6-49, (2)) . See Thrust Bearing on
page 6-7 for the service limit.
Figure 6-49
2. Remove the two bolts (Figure 6-50, (3))
retaining the camshaft thrust plate
(Figure 6-50, (1)) .
Figure 6-50
3. Rotate the engine in the engine stand so that
gravity causes the tappets (Figure 6-50, (5)) to
drop away from the camshaft lobes.
Note: Rotate the camshaft at least two turns to
“bump” any sticking tappets away from
the camshaft.
4. Slowly pull the camshaft (Figure 6-50, (2))
assembly out of the engine being careful not to
damage the front camshaft bushing.
Note:
• If the engine is not installed on an engine repair
fixture, stand the engine upright on the flywheel
end mounting flange. Rotate the camshaft at
least two turns to bump the tappets out of the
way to prevent the tappets from interfering with
the removal of the camshaft.
• The tappets are “mushroom” shaped and must
be removed from inside the engine crankcase.
5. Remove the tappets. Mark the tappets so they
can be reinstalled in the same location.
6. Remove the camshaft drive gear
(Figure 6-50, (4)) only if the gear or camshaft
require replacement. Use a knife-edge puller
and a press to remove the gear. The gear is a
shrink-fit and will need to be heated to 356 -
392 °F (180 - 200 °C) to remove.
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K0002085A
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K0001710B
K0001966
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