ENGINE
6LPA Service Manual
5-91
Valve Clearance Inspection and Adjustment
12/05
© 2007 Yanmar Marine International
Valve Clearance Adjustment
1. Loosen (Figure 5-221, (1)) the lock nut on the
valve bridge (Figure 5-221, (2)) and adjust the
adjusting screw (Figure 5-221, (3)) until the two
bridge heads come into contact with the two
valve stem heads.
Note: Secure the valve bridge using a wrench
and loosen the lock nut. NEVER apply
any torque to the valve bridge.
Figure 5-221
Figure 5-221
2. Loosen the lock nut on the valve rocker arm and
then the adjusting screw.
3. Insert a 0.20 mm feeler gauge
(Figure 5-222, (1)) between the adjusting
screw (Figure 5-222, (2)) on the valve rocker
arm (Figure 5-222, (3)) and the valve bridge for
the intake size and a 0.50 mm feeler gauge
(Figure 5-222, (1)) for the exhaust side.
Figure 5-222
Figure 5-222
4. Turn the adjusting screw (Figure 5-222, (4)) on
the valve rocker arm, slightly slide the feeler
gauge, and lock (Figure 5-222, (5)) the
adjusting screw by the lock nut.
5. Check that the resistance of the feeler gauge is
the same when the feeler gauge is inserted and
the adjusting screw on the valve bridge is
loosened (Figure 5-223). If not, readjust using
the procedure in the following steps 7 to 9.
Figure 5-223
Figure 5-223
1 – Slide Feeler Gauge
2 – Loosen Adjusting Screw
3 – Adjusting Screw
4 – Valve Bridge
(2)
(1)
(
3
)
(1)
0005220
(1)
(5)
(4)
(2)
(
3
)
0005221
(1)
(
3
)
(4)
(2)
0005222