Hitachi ZAXIS 30U-5N Operator's Manual page 270

Check mounting bolts for looseness
Confirm that the compressor mounting bolts and other
mounting/fastening bolts are securely tightened.
Check compressor and fan belt
Visually check the compressor and fan belts for looseness
and wear.
Check fan belt tension by depressing the midpoint of the
belt with the thumb. Deflection must be shown in the right
figure with a depressing force of approximately 98 N (10
kgf ).
If any abnormalities are found in air conditioner system, see
your authorized dealer for inspection.
Adjust Compressor Belt Tension
1. Loosen lock nut (2) of tension pulley (1).
2. Move tension pulley (1) by adjusting bolt (3) until
tension is correct.
3. Securely tighten lock nut (2) of tension pulley (1).
Tightening Torque : 41 to 50 N·m (4.1 to 5.0 kgf·m, 30 to
IMPORTANT: When a new belt is installed, be sure to re-
adjust the tension after operating the engine for 3 to 5
minutes at slow idle speed to be sure that the new belt
is seated correctly.
MAINTENANCE
37 lbf·ft)
Fan Pulley
Depress
[Approx. 98N
(10 kgf, 22 lbf)]
Tension Pulley
Sag:
8 to 10 mm
(0.32 to 0.39 in)
Compressor Pulley
3
7-90
Crank Pulley
1 2
Compressor Pulley
Alternator
Pulley
M1M7-07-013
M1NE-07-005