96 850 ac issue

[2forty]

My 96 850 AC works and blows cold, then quits. I turn it off for a minute or two then turn it back on and it works for awhile. I sometimes can get it to come back on by turning the switch to auto. It can work all day and then some days turn on and off many times. Does this appear to be the thermal switch acting up?
Thanks
2forty

[abscate]

The classic Volvo intermittent AC is caused by clutch gap wear. You can measure this and fix this cheaply by searching this Forum for ‘ bread clip fix’ or ‘ zip tie fix’

[Chuck W]

The "wire fix" has been working for us on both cars for a while now, also.

[2forty]

Thanks

[rguzz]

I got a couple of seasons out of the wire fix, then had to replace the compressor. It was the original, of course.

[oragex]

I got a couple of seasons out of the wire fix, then had to replace the compressor. It was the original, of course.

If the gap is the issue, just remove the pulley (replace the bearing at same moment, use only a good brand) and remove one or two shims. There is no need to replace the whole compressor. Of course, the compressor may go bad for other reasons which will require replacing it, but for the gap issue just undo the pulley.

[rguzz]

I was never fully convinced it actually needed replacing, I'll never know now. All good until this summer, now less cold than last year, so something is up again. But just doesn't blow cool enough, no gap related symptoms. The OP sounds like a clutch-gap problem, yes.

[abscate]

22 years is pretty good evaporator life if you haven't replaced it.

200-300 in parts, 10 hours stupid labor...beautiful cold AC

[Clemens]

OP, I´d start with the ziptie fix. You just need a few zipties of different size and thickness to finetune. And a feeler gauge.
If that fixes it, you can keep the zipties (I´ve had them in 2 of my cars for 2 years or so w/o problems) or reshim the clutch orreplace the compressor. If that doesn´t fix it (or the gap is within specs to start with) you might be low on R134 (refrigerant). Then I´d have a shop evacuate the system and check how much gas is left inside (after 2 years I had 400 grams inside, should have been around 750-800). Then refill and see if the AC works accordingly. If you lose the gas quickly you will need a new evap as abscate suggested.