96 850 T AC clutch

My AC works great as long as the outside temp. is below 85° F and I'm not
stuck in traffic then it blows warm air and usually will not resume cooling.
I bypassed the high temp switch but the problem continues. I was told that
the clutch was worn and the entire compressor had to be replaced?? Can the
clutch be repaired or replaced? The car has 260000 miles.
Thanks
John

 

Sorry for my English, but i'm italian.
You must adjust the distance of the clutch. I don't know what is the correct
gap but I'm sure that is the solution. Ask at your dealer for this.
By

 

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Hi John,

I had a similar problem about 18months ago on my '96 850. It turned out to
be a "temperature sensitive" pressostat switch. That's the pressure switch
on the firewall that controls the compressor on/off cycling.

When it got hot it would fail to turn the compressor on. Generally, if the
a/c was turned on while the car was cold, say first thing in the morning, it
would work ok even in 40deg C outside temp. The cold return gas from the
evaporator kept it cool. But if stuck in traffic or the engine turned off
for even a few minutes, the exhaust manifold would heat it to where it would
fail to operate.

You can check for this by pulling off the pressostat plug and putting a
short circuit across the two pins in the plug (with the motor running),
while your a/c is not working properly. The compressor should run and the
a/c work.

The pressostat can be replaced without de-gassing the a/c. It has a
"schrader" type valve under it. Mine was really tight though. It also cost
about AUD120 (from Volvo).

My high temp switch also failed a couple of weeks later, so I bypassed it
and things are still ok after 18 months.

regards
barry