Yanmar 3TNV82A Service Manual page 187

Measuring and Adjusting Valve Clearance
• If adjusting each cylinder individually, the
cylinder to be adjusted first does not have to be
the No. 1 cylinder. Select and adjust the
cylinder where the piston is nearest to the top
dead center after turning. Make adjustment for
the remaining cylinders in the order of firing by
turning the crankshaft each time.
• To decrease the number of rotations required
to check all cylinders, other cylinders can also
be checked as indicated in the chart below.
Cylinder No.
Valve
No. 1 Cylinder at TDC
Compression
No. 1 Cylinder at TDC Exhaust
Cylinder No.
Valve
No. 1 Cylinder at TDC
Compression
No. 4 Cylinder at TDC
Compression
TNV DI Service Manual
3-Cylinder Engines
1
Intake Exhaust
•
4-Cylinder Engines
1
Intake Exhaust Intake
• •
Example: On a 3-cylinder engine, with the No. 1
piston at TDC on the compression stroke (both
valves closed), the valves indicated on the top line
of the chart can be adjusted without rotating the
crankshaft. To adjust the remaining two valves,
rotate the crankshaft until the No. 1 piston is at TDC
on the exhaust stroke (exhaust valve only open).
2
Intake Exhaust
• •
2
Exhaust Intake
•
• •
ENGINE
3
Intake Exhaust
• •
3 4
Exhaust Intake Exhaust
•
•
•
•
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