Automotive Air Conditioning Information Forum

I have a 2001 Dodge Ram 2500 diesel with a bad a/c clutch and need to find the right part. The problem is the compressor is not original, I had it replaced in 2008 at a shop. I have no idea if they used OEM or aftermarket. Looked at the receipt and it just says "Compressor kit." Looking at the compressor itself I don't see any name, number or markings at all. I can see exactly what is broken and I'm sure a new clutch will fix the problem, as long as I can find the right part. I'm hoping someone can identify it from the pics!

Looks a lot like the OEM Sanden SD7H15 with around 100k mi
If the clutch friction surfaces wear and the disengaged air gap gets too large, then the flat springs are flexed beyond their safety limit, the springs fatigue and crack.
This web site often recommends removing adjustment shims to compensate for friction wear so that the static air gap is recalibrated to 0.015" to .025" like new specs.
Sanden sells replacement clutch parts for 80% of the cost of an entire compressor clutch assembly, therefore forget your clutch replacement unless you get lucky at the scrap yard.
Hope this helps
hotrodac

Thanks, that's what I needed to know. Makes sense about the gap being too large - I had noticed for some time now that when the compressor engaged, the clicking sound was louder than it used to be. Guess I'll be searching the local scrap yards or possibly eBay.

Update... Called around to all the local auto parts stores, salvage yards, even the dealer. Always the same story - they only sell the entire compressor. Looking online, I found some sellers that sold only the clutch hub, but when searching for Sanden SD7H15, they clearly didn't look the same as mine. Finally found one that looked identical from the picture, but the description said it was for a SD7V16. Regardless, it sure looked like a match and the description had measurements which were also identical, so I gave it a shot. Came in today and sure enough, perfect match! Slipped it on the shaft, tightened the nut, works like a charm! Tomorrow I'll check for a .015 to .025 gap and adjust the shims if needed so this won't happen again. $40 (including shipping and I requested 2nd day air, part was only $21) and a 5 minute job. Sure beats replacing the entire compressor!

Checked the gap this morning and it's .032 or .007 more than the upper limit. Regarding shims, all I see is a single washer with a thickness of about .030. I was hoping there'd be several thin washers and I'd just remove one or two. Since there is only one, I assume I just need to find a similar washer that is thinner?

Any steel washer can be a shim.

That gap can be .005 - as long as it does not drag when off. Some clutch plates are flatter than others. If you find an .012 shim - toss it in there & try it.

Any U-Pull it junkyard is a good place to grab some shims if you need them.

Thanks, that's a good idea. I kind of thought any steel washer of the same size but thinner would work. Probably could just pick one up at the hardware store. If I leave it as is (out of tolerance and will only get worse as the clutch wears), I'm sure it's just a matter of time before I have another broken flat spring.

Yep. The diesel torque impulse is hard on stuff like that. If the spring is deflected a lot it has a much worse bending moment in the spring.

Your numbers are close - have you tried installing it without the shim & checking the gap? If you can spin the pulley (belt off) with the clutch installed any drag will be obvious.

You are mating two used friction surfaces. It will probably open up .010 in the first month of operation as the surfaces match each other.

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Without the shim there is basically no gap, the pulley doesn't spin freely and you can tell the 2 surfaces are making contact, but just barely. This washer is about .030 and I think I need one that's about .015 and I'll be in business.