Diesel Data: Automotive Repair

Compressor Clutch: Testing and Inspection





CLUTCH PLATE AND PULLEY INSPECTION
Check the plated parts of the armature plate for color changes, peeling or other damage. If there is damage, replace the clutch set.
Check the pulley bearing play and drag by rotating the pulley by hand. Replace the clutch set with a new one if it is noisy or has excessive play/drag.





CLUTCH CLEARANCE INSPECTION
Measure the clearance between the pulley and the armature plate all the way around. If the clearance is not within specified limits, the armature plate must be removed and shims added or removed as required, following the procedure described in Compressor Clutch/ Service and Repair.

Clearance: 0.5 ± 0.15 mm (0.020 ± 0.006 in)

NOTE: The shims are available in four thicknesses: 0.1 mm, 0.2 mm, 0.4 mm, and 0.5 mm.





THERMAL PROTECTOR INSPECTION
Release the compressor clutch connector from the connector holder.
Check the thermal protector for continuity. There should be continuity.
If no continuity, replace the thermal protector.





CLUTCH FIELD COIL INSPECTION
Check the field coil for resistance.

Field Coil Resistance: 3.2 ± 0.15 ohm at 68°F (20°C)

If resistance is not within specifications, replace the field coil.