AC compressor clutch replacement

[willw]

The belt on the AC pump broke yesterday, when it went it took out the AC clutch wiring connector. Melted/ground it in two.
My system is still a virgin R12 unit and I just filled it with NOS R12 a couple of days ago. I don't want to open the system and lose the R12 as I've only got 2 cans left. So has anyone managed to get the clutch off the pump without taking it out of the car? The manual says to drain the system and remove the pump then using special tools pull the clutch off. Am I stuck?

[97 SL320]

As long as there is room to work, the compressor clutch can be changed in the car.

What type of compressor are you using?

[willw]

As far as I know it is the OEM version that came with the car.

The manual says that I need special tools to pull the clutch off the pump. Do I really need them or are there substitutes available? Can I make them?

So if I have to pull the pump I might as well replace both the pump and clutch and convert to R134. Can anyone tell me the consequences of that?

Thanks

[97 SL320]

I don't know this car specifically, but am guessing it has a GM R4 ( As in General Motors )

If so, to pull the clutch plate you need a puller and a reinstaller. The clutch plate is pressed onto the shaft and, the retaining nut adjusts the air gap. If you fully tighten the nut the plate will bind and keep the compressor fully engaged.

[Phillytwotank]

You will be disappointed with r134 compared to the original.

[Charlie Foxtrot]

Bought my R4 compressor clutch tools off the Snap On truck when the R4 was introduced. By now i'm sure there are imitations. Or you can rent them at AZ or other parts stores where you buy the clutch.

[willw]

Thanks!
Autozone tool rentals. I didn't know they would have the pullers for rent. But then again I didn't know that the compressor was a GM R4 until just now.

[97 SL320]

The puller ( and installer ) are a big bolt in a little bolt.

The puller threads into the face of the clutch plate. The installer threads onto the compressor shaft and pulls the plate on. Be sure to get the plate clearance spec.

Many of the GM spec compressors have bolts along the edge of the pulley ( they are crimped to lock them. ) From what I recall they don't need to be removed unless the pulley is small enough that the clutch coil won't come out the back.

Once you get the clutch / pulley and coil off, DO NOT remove the 4 bolts that hold the snout to the compressor, if you do the freon charge will leak out.