I don't think any pictures needed.

Pry out the AC belt off its pulley by wedging a screwdriver at where the belt meets pulley WHILE turning the crank bolt clockwise with a wrench. Done in less than a minute. This way you don't have to mess around the compressor's belt adjustment arm. Install the AC belt later using this way. The only caveat is this might crack the belt's rubber if it has harden enough. Have a new AC belt ready. Same size.

Amarin.

Once I have everything in place with the belt tensioned and the bolts tight I always back off the tensioning screw a few turns to relieve the stress on it.

Randy
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Any twenty minute job is just a broken bolt away from a three day ordeal

I took a quick look for something simple here in the FAQ or a simple youtube video or series of pics to help you deal with the A/C compressor belt, but nothing jumped out at me as appropriate so I'll resort to trying to describe the basics here. Perhaps someone will take a moment to find and post a pic to go along with this description:

o Attaching to the top of the A/C compressor are two slotted tension adjustment arms, one forward and one on the rear (which you may well have not noticed if you have been having problems). Note that the forward arm has the long threaded 10mm adjuster bolt secured in place with a 13mm locking nut on a retainer bolt. The rear arm has a similar 13mm locking nut on a short carriage bolt in line with the front retainer bolt.

o You need to throughly loosen both those 13mm nuts. The forward 13mm nut is relatively straightfoward to access, but the rear one is often a pain to deal with, especially if you don't have appropriate tools. You can try to get a 13mm box wrench on that nut, but may not be able to get enough leverage to free it if the wrench doesn't position properly and the bolt hasn't been loosened in a while, plus there is often A/C plumbing in the way. A 13mm socket on a 3/8" drive ratchet wrench is usually what's needed for the job, but the ratchet head will usually be too fat to get it in properly above the compressor (smaller 1/4" drive ratchets aren't up to this job). Most people are able to use a 3/8" universal joint or a 3/8" extension at a slight angle to get the socket over the nut, but what's best is a wobble extension you can properly use at a slight angle. This is about the only place on the car where I always try to have my wobble extensions out and on hand.

o Once those 13mm nuts are loose you then back off the long 10mm adjuster bolt as far as you need to in order to push the top of the A/C compressor in toward the block to loosen the belt. You will likely need the aid of a length of wood or carefully use a pry bar to force the top of the compressor in toward the block as far as you can. Just be careful of the compressor plumbing and the electrical connector on top. Note that the opposite end of tensioning arms are fixed to the block mounting bracket with short bolts (12mm as I recall). If there isn't enough freeplay in the adjuster slots to allow the compressor to be moved in then you may need to totally remove the two 13mm bolts and/or loosen the far inward two 12mm bolts in order to get the compressor in a bit further (just don't forget to later re-tighten the 12mm bolts if you loosen them).

o Depending on the size of the installed A/C belt, even when pushed in as far as you can, the belt usually won't be anywhere near loose enough to get off by hand. You will need to rotate the crankshaft (clockwise, with a 24?mm socket on the crank pulley) and walk the belt off the compressor pulley (using a slot screwdriver or a belt tool made for the job to pry the leading section of belt up over the lip of the compressor pulley to start walking it). In extreme cases, when the A/C compressor won't go in far enough, you may have to go underneath the compressor and remove the lower pivot mounting bolt at the bracket to be able to move the lower part of the compressor in as well, but by that time it's usually just as fast to cut the belt and replace it with a new one of more appropriate length. Note that A/C belt size is good for a whole other discussion.

o When working in the compressor area it is often well worth the effort to remove the above alternator and swing it out of the way so you can better see what you're doing and have much improved access to everything, especially the first time. I've taken to now doing this as a matter of routine as it cuts down on the contortions and the skinned knuckles trying to get at some of those compressor mounting bolts. Just be sure not to short the wires on the back of the alternator to metal when it's lying loose.

[Edit: I just noticed Spook's reply while I was composing this suggesting removal of the belly pan and working from below. This shouldn't be needed unless you need access to the lower A/C mounting pivot bolt. Unless it's up on a hoist, it's generally far more convenient to work from above as I've described. Only once when I had to go for that lower pivot bolt on a B234F 16-valve did I go from below.]

o When you go to re-install the A/C belt, you may wish to refer to the following recent brickboard thread RWD: A/C pulley not lining up [900]
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Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now

Dear onlyVolvo,

Hope you're well and stay so. If you're time-crunched, cut the air-conditioning (a-c) drive belt, replace the alternator belt and drive the car.

Unless you know that he a-c belt has recently been replaced, i.e., that it is "fairly new", it may be due for replacement. The drive belts should be replaced "as a set". They "live" in the same environment, so age at the same pace. Depending on where the car lives, the a-c belt may be used little, or a lot. But the rubber still deteriorates with time/exposure to the elements.

Remove the belly pan. At the top of the compressor, there are adjustment arms, that - when their bolts are loosened - allow the top of the compressor to be pushed towards the engine. That movement slackens the drive belt just enough to allow removal.

Loosen the bolt that secures the tensioning arm (a flat piece of metal with a long slot). Then, turn the tensioning arm screw - a long hex-head machine screw with a 10mm head - to allow the compressor to be pushed towards the engine.

Then, loosen slightly the bolts at the bottom of the compressor, which bolts secure the compressor to the mounting bracket.

That will allow just enough movement to remove/install the a-c belt. I usually use a round-shaft screwdriver, "to work" - to lever - the a-c belt onto the compressor's pulley.

Once the new belt is in place, turn the tensioning arm's screw to take-up slack in the new belt. As the belt is "short", it is properly tensioned when it can be depressed 1/8" in the middle, when you press on it with your index finger.

An over-tight belt will stress the compressor's clutch/bearings. A too-loose belt will slip and so wear prematurely. That's better than risking damage to the compressor.

Hope this helps.

Yours faithfully,

SPRAY BLASTER ON THE ADJUSTEMENT BOLTS,,YOU CAN LOOSEN THE BOLTS THAT HOLD THEM TIGHT THEN I THINK TURN COUNTER CLOCKWAYS ..TO SLACKEN TO REPLACE BELTS