Ok.. I'll check again to see....I'll let you know.............

 

I was reading this thread with interest, because last weekend, we bought a 2000 S70 with high mileage, and the A/C worked great on our test drive. This week, it got warmer, and the A/C quit cooling after driving 20 minutes or so one day. It would start working again after I shut it off for several minutes, but then wouldn't keep cooling very long.

I thought at first the freon might be low, but after it cooled great for the first 15 to 20 minutes each day, I realized that couldn't be the case. It cools really well when it is working.

Just to satisfy my curiosity, I paid $10 for a new A/C compressor relay today, but of course, that didn't solve it.

Then I jumped on this forum and started searching. I read with interest in this thread the suggestion that the compressor clutch might not be shimmed correctly, and that you could test that with a broom handle. I drove the car a short period until the A/C quit working, drove back home and tried it. It worked! I tried it again and it worked again.

So now I need to read up on the shim procedure to see if it is something I want to try, but at least I know what the problem is. I feared some electrical item might be heating up, and that it could be difficult to diagnose. I was also wondering if the ECC system was going bad. I didn't want to think about that.

I'll try to write again if I succeed in doing it myself. It's great that I may have found the solution my first time on this forum!

 

Hi and welcome to the site.

The gap on my compressor was bad and I went the zip tie route. It took me about 1-1/2 hours to get those freeking zip ties on it and I marked up the back of my hand a little doing it. If I had to do it over again, I would drop the compressor a little and take the front of the compressor off and do the washers (correct peramant fix).

 

Shimming is one common issue with the compressors, but having read a bucket load of posts on it, it seems the same symptoms point to two main culprits. The shim gap, and low gas.

Mine was low gas, after about 20 minutes my overheat sensor on the compressor was tripping as there was not sufficient gas to keep the compressor cool. It would turn off for about 3 minutes then switch back on.

I was going to do the shim job, but a mate of mine offered to regas the car, and at no charge if it didn't fix the problem. Have had ice cold air now for almost 3 months.

 

when you say "no gas" your talking about freon yes? just want to be sure I got the meaning right.

I have this issue but mine isnt really time related. it happens when I get on it and the ac has been running which is a sign of the shim issue I read.

 

Finally I found the problem with my a/c, before the compressor engaged for about 10 or 15 minutes then shut down then engaged. I did reshimmed everthing ok good gap and nothing. So I changed my LOW SIDE PRESSURE SENSOR and that worked perfect.I never think that was the problem in my car now I am happy with a/c working .

 

I think this reshimming factor is blown way out of portion. I have had to work on four friends 850's that a/c work for a short time and then quit blowing cold(as in compressor was not cycling). All four showed less than 12v going to coils. Wiring a 4 dollar relay to coil wire solved the problem. The last one I rewired over a year ago is still cooling.

 

I need to sold my issue as well. works fine until I gun it.

 

i have a 95 850 with dual climate control the ac works fine sometimes and not at all others if i turn the vehicle off when it's working it stops working any suggestions also how do i find the blend door

 

If freon levels are good and gap is good and this problem only manifests in Hot Weather. Try this.

 

Yeah mine is just clickn on then off, or at least that's what I hear under the hood. I'm assuming no R134 at all. This noise might be indicative to the aforementioned reasons.

 

Low charge or a bad cooling fan.

- Tim

 

If it's empty, it won't run at all - that destroys compressors, and is what the low pressure cutoff switch is there to prevent. Hoses have some porosity, so needing a recharge/topup every 5 years or so is not unusual. My 850 is about on that schedule, and I have no detectable leaks.

- Tim

 

I did the compressor shim fix today. (Should be called a de-shim as you actually remove one of the 3 shims). I used this as a guide: Volvo AC Pump Shim

For those reading this thread trying to figure out an A/C problem you should always diagnose the problem before either trying this fix or throwing money at your car. My symptoms were a perfectly cold A/C system which would suddenly quit working for no apparent reason but only in high demand situations like a very hot day or stuck in traffic. When measured the gap between the clutch and pulley was about 1mm. The proper range is about .4mm to .6mm. I removed the thickest shim to bring my gap down to about .5mm.

Lessons learned for a 2005 S40 T5. Once you remove the pax side wheel, wheel well liner, and under car cover the compressor is easily accessible. You don't even need to remove the serpentine belt. Also, the link above shows the author using a home-made clutch puller. I used a crank gear puller. You could even use the three M5 x .8 thread holes with 50mm or longer bolts to gently pop the clutch free. You would need to be careful with even pressure so that you do not strip the threads. M5 is quite small and the flange is not very thick.

 

For those that may need it, here is a video that shows you how I serviced my AC system with freon:

 

got a problem with a/c runs good for about 30 minutes then stops if you stop shut the engine down and restart it comes back on the a/c its self gets cold any one tell me what i should looking at to fix the problem

 

Dragon0622, have you read through the thread or just tacked a question on to the bottom of it ??

Maybe this might answer your question: https://volvoforums.com/forum/volvo-...uts-out-42326/

 

Im sure your answer is in this thread if you read any of it.

sounds like your clutch needs shimming. if you cant do that then you can do the plastic bread tie fix or you and get some small zip ties and do the same basic patch. I am using zip ties myself and works great. I used washers before but eventually the glue gives way and you have to repeat the process.

takes less than 30 minutes max to fix...I mean bandaid but its better than no ac at all.

 

Someone had replaced the alternator on my '91 740 Turbo Wagon and forgot to replace the ground wire directly to the A/C compressor and because of that my A/C would cycle just like yours. A ten minute reattachment of the ground and mine is working just fine.