After car warms up ac cycles on and off if car is in gear.

Post by **thecheat** » 07 Sep 2010, 15:10

I narrowed down my ac problem... If my car has heated up to operating temp, and the car is in drive, and my foot is not on the gas, the ac clutch will always go on and off. If the car is in drive and I'm giving it a little gas, the ac clutch is always on.

It doesn't seem to be electric load dependent, i can be in park with everything electric on and it's ok, but shift to drive and it acts up. I was doing this today and shifting to neutral at traffic lights kept the air on.

Alternator outputs 13.65 volts.

If I push the throttle plate further closed (obviously it doesn't go far but it seems to affect idle) then i can disengage the clutch at will. The idle drops just enough I guess.

Does the alternator need a rebuild to bring the voltage up? It seems to be a problem with volts at idle.

Any thoughts?

Post by **renns** » 07 Sep 2010, 15:41

Check clutch gap. As the clutch gets hot, it has a harder time holding itself engaged. If gap is over spec, and voltage is low at idle, you may see that problem. Shimming behind the three stops on the clutch is a quick and easy solution. Do a search on bread clips, and you'll find the thread.

Post by **thecheat** » 07 Sep 2010, 18:22

Well I do know the gap is too much but would it really cause the electromagnet in the clutch to disengage completely instead of just slipping?

I'm going to either do the bread clips or just reshim it by removing the clutch. If i thread the bolts in and pop the clutch out, it will be possible to do it through the wheel arch, right? I don't know why everyone wants to do the bread clip fix if threading on three bolts and popping the clutch off is only a little more work, unless there is no room to remove the clutch nut with the compressor still installed?

Post by **jblackburn** » 07 Sep 2010, 18:33

My alternator only puts out like 12.9 V, and it's enough to keep the compressor clutch engaged at idle.

That was in the middle of winter, and I haven't tested/replaced it since - hard-pressed for time/dinero, but it has been working fine all summer.

I believe the whole thing has to be removed, or at least dropped down to get to the clutch. Try pressing on it with some sort of stick or something at idle and see if you can get the compressor to stay running instead of clicking in and out.

Post by **thecheat** » 07 Sep 2010, 19:11

Well I'm going to look at it when I do the timing belt in a couple weeks. I had the same problem on my Taurus sho and the compressor was at the top of the engine and was easy to get to. I don't have any feeler gauges gut i put some flat stock in the gap and it is at least .8mm so I for sure have to shim it.

I will look and see if there is any way to remove the clutch without removing the compressor though.. Such a shame if you have to do so much extra work because they couldn't spare an inch or two in the engine compartment.

Post by **jblackburn** » 07 Sep 2010, 19:19

Ah, it would need to be removed for that.

http://volvospeed.com/vs_forum/index.ph ... ntry992918

and

http://volvospeed.com/vs_forum/index.ph ... g-problem/

An inch or two to spare...you've never owned a Honda Civic or Accord before they were offered with a V6 engine in the same car, have you? I swear, the things have to be worked on by mice.

Post by **thecheat** » 07 Sep 2010, 19:41

I was looking at a PDF someone made and it looks like bread clips for me... I'll be doing the timing belt and water pump in the hot sun so no way am I messing around with dropping the compressor on the same day.

Post by **renns** » 07 Sep 2010, 21:22

Shims with some adhesive to hold them in place is a well-proven and inexpensive solution if excessive clutch gap is the source of your problem. I shimmed mine in the spring, and the AC has been trouble-free since - a real relief as we had a hot summer up here! If you're already in there working on the timing belt/water pump, it'd only take a few minutes to shim the AC.

Post by **jreed** » 08 Sep 2010, 04:53

I did the shim trick too, first with bread bag clips and Duco cement. This lasted about 10 miles -- the clips did not adhere well to the glue. I cleaned out the old glue, cut out some brass shim stock that was the right thickness (about 0.4mm or so) and used crazy glue to hold the brass in place. This has been working well so far for about 2-3 months (~1.5 k miles). Good luck!

Post by **thecheat** » 08 Sep 2010, 05:13

You have a good idea there with the brass stock. My local hobby store has lots of different size brass stock for model building in various remeasured thicknesses. Maybe the brass could be cut to fit and be bent or safety wired in such a way that it would not be flung out.