Yanmar 1GM10 Operation Manual page 62

PERIODIC MAINTENANCE
Checking and Adjusting the
Alternator V-Belt Tension
Inadequate V-belt tension will cause
reduced electrical power generation and
increase the wear on the belt. Too much
V-belt tension can cause damage to the
alternator bearing.
WARNING
Perform this check with the key
removed (the power switch off) and the
battery switch turned off to avoid
contact with moving parts.
Never get any oil on the belt. Oil on the belt
causes slipping and stretching. Replace
the belt if it is damaged.
1. Inspect the V-belt for any damage or
wear and replace it if necessary.
2. Find a location on the belt that is in the
middle of the two pulleys.
3. Check the tension by pushing on the
middle of the belt.
With proper tension, the belt should
deflect 8 to 10 mm (approximately
3/8 in.).
4. Loosen the alternator bolt and move
the alternator to adjust the V-belt
tension, as required.
5. Hold the alternator in position and
tighten the bolt.
6. Recheck tension by repeating step 3.
56
Inspecting and Adjusting the
Intake / Exhaust Valve Clearances
Proper adjustment is necessary to
maintain the correct timing for opening and
closing the valves. Improper adjustment
will cause the engine to run noisily,
resulting in poor engine performance and
engine damage. Consult authorized
Yanmar Marine dealer or distributor to
adjust the intake / exhaust valve
clearances.
Inspecting and Adjusting the
Throttle and Shift Control Cables
Various control levers and cables on the
engine and marine gear are connected to
the throttle and shift control console. The
entire assembly loosens and stretches
with prolonged use and initial break-in
movements. It is dangerous to operate
under these conditions. The throttle and
shift control console should always be
maintained in proper adjustment and
should be inspected periodically.
The high speed stop bolt on the engine
governor is set at the factory. Do not
adjust. Adjustments to this bolt will void the
engine warranty.
Adjusting the Governor Control Cable
1. With the engine off, move the throttle
lever to the high speed position.
2. Check the governor control lever on the
engine and verify that the lever is
making contact with the high speed
stop bolt.
3. Move the throttle lever to the low speed
position.
GM Series Operation Manual