Check Alternator Drive Belt Tension, Adjust - Komatsu D475A-5E0 Operation & Maintenance Manual

SERVICE PROCEDURE

CHECK ALTERNATOR DRIVE BELT TENSION, ADJUST

CHECKING
Push a point midway between drive pulley (1) and alternator pulley
(2) with a finger to check the tension. Deflection (A) when 1 belt is
pressed with a finger force of approx. 59N (6 kg) should be approx.
15 mm (0.59 in).
ADJUSTING
1. Loosen nuts (2) of adjust bolt (1) and mounting nut (3) (at 3
spots).
2. Turn nut (4) clockwise, then move alternator (5) to adjust the
belt tension so that the deflection is approx. 15 mm (0.59 in)
when pushed with a force of 59N (6 kg).
REMARK
When adjusting the belt tension, never push the alternator directly
with a bar. If it is necessary to push the alternator, insert a piece of
wood in-between and push it with a bar.
3. Tighten loosened nuts (2) and (3) to secure alternator (5) (at 3 spots).
4. Check for damage to the pulleys, and wear of the V-groove and V-belt. Be particularly careful to check that the
V-belt is not in contact with the bottom of the V-groove.
5. If any belt has stretched and there is no allowance for adjustment, or if there are cuts or cracks on any belt,
replace the belt.
6. After replacing the belt, operate for one hour, then adjust again.
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MAINTENANCE