FZJ80 A/C Compressor Pulley Misalignment (1 Viewer)

[TXIN]

Hey guys,

Has anyone had issues with aftermarket A/C compressor pulley alignment? I'm baselining a 96 FZJ80 that I bought a few months ago and when I went to replace the belts, I noticed that the belt for the compressor had been eaten up pretty good. On further inspection, the compressor pulley is recessed about 1/2" as compared to the proper groove in the crank and my new A/C belt tensioner pulley.

I have no real history on the truck but a functioning A/C system with a new compressor was a selling point for me so I'm a bit disappointed at the moment. I can only assume the P.O. purchased a cheap one though, based on his other repair work I've seen so far. Unfortunately, I can't find a part number on the compressor to verify if it's the correct part or not.



Thanks in advance.

 

[John Mc]

I Had this happen to me. Wish I had a solution for you. I ended up replacing It with a Denso.

 

[Malleus]

Unfortunately, there is no adjustment on the fore/aft position. If it doesn't line up, you have no choice but to replace it.

I think all the aftermarket clones are either rebuilds, or are based on the castings from the Denso models. The position of the pulley is determined by the machining of the spindle (and its position in the casting); if that's off, the pulley will be off by the same amount.

Short of remachining the pulley, or installing a bushing cut to the correct internal dimensions, you're SOL.

If someone's found a way to fix this problem, I'd love to hear it.

 

[Malleus]

Since you're stuck, if you have the time and interest, you might try fixing it yourself. It already doesn't work, so you really have nothing to lose except your time. And maybe some knuckle skin. The clutch assembly can be removed from the compressor, without purgring the system, which you'll have to do if you replace the compressor, along with the dryer. The process is a small PITA with the radiator in place, but it's much cheaper than the cost of a compressor and dryer, plus purging and recharging the system (you're looking a a minimum of $500 there, and that's a good price).

The disassembly procedure is in the service manual.

The snap ring keeps the clutch in place, and the wavy ring retains the pulley. If you can find some spacers that will move the pulley far enough forward, and have someone cut the pulley bushing down for you, you might be able to get it to work. From the picture it looks like you're within 1/16"; I'd take careful measurements before I broke it down. This sounds like a lot, but I promise you it's cheaper than the alternative.

Fortunately, you're too far back and not too far forward, which would be unfixable, without tearing the pump apart.

 

[TXIN]

John Mc:

Thanks for chiming in, I appreciate knowing I'm not the only one...sorry to hear you had to replace the compressor though.

Malleus:

Thank you for all of the technical advice! As you said, I don't have much to lose by trying to fix the current compressor so I may very well go that route if there is a way. To clarify, would the spacer need to be between the electromagnet and the pulley? If this is the case, would there be any decrease in the magnet's ability to pull the front clutch drive plate into the pulley given the added distance? I'm assuming the needed machining of the pulley bushing (bearing?) would be on the front side so that the wavy snap ring can still seat in the groove on the compressor snout with the new spacers behind the pulley? I guess I'm having a hard time understanding that part because the pulley rides on a bearing and I'm not sure how one could do any machining to the bearing itself, especially because the wavy snap ring appears to be larger in diameter than the race portion of that bearing. (Photo attached) I'm a complete novice when it comes to A/C components and will happily accept any education you have to offer!

I do wonder if the discrepancy could also be the result of the pulley design itself. It seems theoretically possible that the machining on the compressor snout is fine and that the pulley casting is a little off. What do you think? I'd be tempted to try measuring the distance between the face of the pulley and the belt groove and compare to someone's Denso or OEM version. If it's as simple as that, I could just replace it with the 88412-22070 shown above.

 

[mudgudgeon]

The pulley on the compressors can be removed and swapped around.

My first 80 needed a new compressor, I bought a lot of three NOS Denso compressors off ebay gambling that at least one would work.
I had one with the correct body, but wrong pulley offset, and another had the correct pulley offset, wrong body.

Mixed and matched to make one work.

 

[TXIN]

Ok, that kind of confirms what I was thinking mudgudgeon. Seems to me that it's more likely a pulley issue than a casting/machining issue, but again I'm no expert. I just can't see how altering the location of just the pulley with a spacer wouldn't affect the front plat and magnet's operation as well.

 

[Malleus]

As I said, I've never tried it, so I haven't done any more thinking about it than what I put into my post (which wasn't much). @mudgudgeon is probably onto the root cause; as I said, I think all the pump castings are from the Denso original, so I'd doubt that's the problem.

Hit up @slow95z and see if he has a compressor that's shot that he's willing to let you have for parts, and try that pulley; it's likely to be a Denso, so that may give you some insight into whether a new pulley is warranted. Or, you may be able to use the pulley from the parts compressor, and save the money you'd otherwise spend on a new one.

 

[mudgudgeon]

Yes, magnetic clutch hub portion was the same on all the ones I had, but the pulley is a separate ring, and they had different offsets.

Sourcing a busted original compressor/pulley might be an option. Swap it onto the compressor you have

 

[TXIN]

Thanks, that's a good point. A used OEM is probably a good idea even if it's just for reference. Interestingly, an eBay ad I found for an aftermarket clutch kit (not one that I would buy though) states explicitly that it only fits OEM Denso compressors and not aftermarket. Makes me wonder what the potential difference in the pump body/machining itself is.