PC800, 850-8 21
30 Testing and adjusting SEN00786-02
Testing and adjusting
alternator belt tension
Testing procedure
1. Open the engine compartment cover on the
counterweight side.
2. Measure the belt deflection (a) when pushing a
point midway between the alternator pulley and
the drive pulley with the finger.
a Deflection (a) when pressing force is approx.
58.8 N {approx. 6 kg}: 13 – 16 mm
Adjustment procedure
a Adjust the belt according to the following proce-
dure when the belt deflection is not normal.
1. Loosen nuts and bolts (1), (2), (3) and (4) in this
order.
2. Turn nut (5) to move alternator (6), and adjust
the belt tension.
a Nut (5):
• It is moved to the side that belt is loos-
ened when turning it clockwise.
• It is moved to the side that belt is ten-
sioned when turning it counterclockwise.
a Test for breakage of each pulley, friction of
V-ditch, friction of belt, and contact between
belt and V-ditch.
a Replace it with new belt if it was too
stretched so that adjustability was lost, or cut
and crack occurred.
3. Tighten nuts and bolts (4), (3), (2) and (1) in this
order.
a When the V-belt was replaced, measure its
deflection again after one-hour operation
and then readjust it if necessary.