Komatsu PC118MR-8 Operation And Maintenance Manual page 339

MAINTENANCE
2. The check is manual and involves pressing the belt with
y our thum b at an i ntermedi ate po int between the
compressor pulley (2) and the crankshaft pulley (3).
Deflection (A) should be 5-8 mm when the belt is pressed
with the thumb with a force of approx. 58.8 N (6 kg).
3. If the deflection exceeds this value, adjust by proceeding
as indicated below.
NOTICE
Guards are installed in the area of the engine to protect
personnel from moving parts.
These guards should only be removed by a Komatsu
service engineer unless specific instructions are given in
this manual.
Adjustment
1. Loosen the screws (1) and (2).
q Bracket (4) holds the compressor in place. When bolts
(1) and (2) are loosened, bracket (4) moves with the
bolt (2) securing position as a fulcrum.
2. Loosen the nut (5) fastened to the fixed bracket (3) and
tighten the screw (6).
3. Tighten the screw (6) until a 5-8 mm bending (A) is
obtained when pressing the belt with the thumb, applying a
force of about 58.8 N (6 kg) in the intermediate point
between the compressor pulley (2) and the crankshaft
pulley (3).
4. Tighten the screws (1) and (2) to fix the compressor.
NOTICE
q Check each pulley for damage, wear of the V-groove,
and wear of the V-belt. In particular, be sure to check
that the V-belt is not touching the bottom of the V-
groove.
q If the belt is stretched and there is no allowance for
adjustment, or if it is cut or cracked, please contact
Komatsu distributor for replacement.
WEAM014802
MAINTENANCE PROCEDURES
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