Yanmar 6LPA-STP2 Service Manual page 102

E N G IN E
10. Measure the outside diameter of the cylinder
head bolt threads using calipers (Figure 5-25).
Inspect the bolts for damaged threads.
• Standard outside diameter: 10.80 to 11.00 mm
(0.425 to 0.433 in.)
• Minimum outside diameter: 10.55 mm
(0.415 in.)
If the measured value is less than the minimum
outside diameter, or the bolt is damaged replace
the bolt.
Figure 5-25
(1)
(2)
Figure 5-25
1 – Thread End
2 – 34 mm (1.3 in.)
Intake and Exhaust Valve Cleaning and
Inspection
1. Remove all carbon deposits from the valves
using a scraper and wire brush (Figure 5-26).
Figure 5-26
Figure 5-26
5-22
2. Measure the inside diameter of valve guides
using a caliper gauge (Figure 5-27).
Valve guide inside diameter:
• 7.010 to 7.030 mm (0.276 to 0.277 in.)
Figure 5-27
3. Measure the diameter of the valve stems using
a micrometer (Figure 5-28).
Valve stem diameter:
0004950
• Intake valve: 6.970 to 6.985 mm
• Exhaust valve: 6.960 to 6.975 mm
Figure 5-28
0004951
© 2007 Yanmar Marine International
Figure 5-27
(0.274 to 0.275 in.)
(0.274 to 0.275 in.)
Figure 5-28
6LPA Service Manual
Cylinder Head
0004952
0004953