Compressor Clutch: Service and Repair
REMOVALCompressor assembly must be removed from mounting. Although, refrigerant removal is not necessary.
Fig. 2 Compressor Shaft Bolt And Clutch Plate:
1. Remove the compressor shaft bolt. A band type oil filter removal tool can be placed around the clutch plate to aid in bolt removal.
Fig. 3 Clutch Plate And Shim(s):
2. Tap the clutch plate with a plastic hammer and remove clutch plate and shim.
CAUTION: Do not use screwdrivers between the clutch plate assembly and pulley to remove front plate as this may damage the front plate assembly.
Fig. 4 Removing Pulley Snap Ring:
3. Remove pulley retaining snap ring with Snap Ring Pliers (C-4574), and slide pulley assembly off of compressor.
4. Remove coil wire clip screw and wire harness.
Fig. 5 Clutch Cell Snap Ring:
5. Remove snap ring retaining field coil onto compressor housing. Slide field coil off of compressor housing.
6. Examine frictional faces of the clutch pulley and front plate for wear. The pulley and front plate should be replaced if there is excessive wear or scoring. If the friction surfaces are oily, inspect the shaft nose area of the compressor for oil and remove the felt from the front cover. If the compressor felt is saturated with oil, the shaft seal is leaking and will have to be replaced.
7. Check bearing for roughness or excessive leak- age of grease. Replace pulley assembly as required.
INSTALLATION
1. Align pin in back of field coil with hole in compressor end housing, and position field coil into place. Make sure that the lead wires are properly routed, and fastened with the wire clip retaining screw.
2. Install the field coil retaining snap ring with Snap Ring Pliers. The bevel side of the snap ring must be outward. Also both eyelets must be to the right or left of the pin on the compressor. Press snap ring to make sure it is properly seated in the groove.
CAUTION: If snap ring is not fully seated it will vibrate out, resulting in a clutch failure and severe damage to the front of the compressor.
3. Install pulley assembly to compressor. If necessary, tap gently with a block of wood on the friction surface.
4. Install pulley assembly retaining snap ring (bevel side outward) with Snap Ring Pliers (C-4574). Press the snap ring to make sure it is properly seated in the groove.
5. If the original front plate assembly and pulley assembly are to be reused, the old shim(s) can be used. If not, place a trial stack of shims, 2.54 mm (0.10 in.) think, on the shaft against the shoulder.
6. Install front plate assembly onto shaft.
7. With the front plate assembly tight against the shim(s), measure the air gap between front plate and pulley face with feeler gauges. The air gap should be between 0.35 and 0.65 mm (0.014 and 0.026 inch). If proper air gap is not obtained, add or subtract shims until desired air gap is obtained.
8. Install compressor shaft bolt. Tighten to 17.5 ± 2 Nm (155 ± 20 in. lbs.).
NOTE: Shims may compress after tightening shaft nut. Check air gap in four or more places to verify if air gap is still correct. Spin pulley for final check.
CLUTCH BREAK-IN
Alter a new clutch has been installed cycle the A/C clutch 20 times (5 seconds ON and 5 seconds OFF). During this procedure, set the system to the A/C mode, engine rpm at 1500-2000 and high blower speed. This procedure (burnishing) will seat the opposing friction surfaces and provide a higher clutch torque capability.