C. A/C Compressor Test

2. Check clearance of electromagnetic clutch. If clearance is less than 0.5 +/- 0.15 mm, then either the compressor drive shaft has axial play or the wobble plate on the drive shaft is loose. Also, the spring plate may be too soft or is loose in the rubber mount (Figure 4).

Note:
Excessive clearance or defective rubber mounts may cause the A/C compressor to shut-off due to erratic rpm signals.

3. Rotate spring plate (arrow, Figure 4) clockwise by hand. If the plate turns with difficulty or does not turn at all, the compressor is defective or is seized.

In those cases, replace the leaking part, the compressor, the compressor lines, the receiver-drier and the expansion valve.

4. If the clearance of the electromagnetic clutch is within specification and the spring plate turns easily check compressor for overheating. If the inner walls of the suction or discharge connections on the compressor (arrows, Fig. 5) are black in color, then the compressor overheated. Replace parts as outlined in 2nd paragraph of step 3.

5. If no evidence of overheating is found, install cover plate (b) with O-rings (18) and bolt (a, Figure 5). Rotate spring plate clockwise, if pressure builds (resistance to turning increases) then the compressor is in operating condition. If no pressure builds up then replace the parts as outlined in 2nd paragraph of step 3.

Note:
Cover plate (b), used for shipping, is supplied on new or rebuilt compressors.

6. On vehicles with engine 102, if the new A/C hose assembly is being installed, the hose must be secured as shown (b, Figure 6). As of April 1987 production (chassis end number 353959) the hose assembly is attached in this position at the factory. The hose can be attached in this position on earlier production vehicles. If the removed hose was previously attached at point a, reinstall the bolt only in this position. If the compressor is not being replaced, install new O-rings (18, Figure 5).