1994 850 new Owner Just Arrived, AC stuck on

COS850Turbo · Post by **COS850Turbo** » 13 Apr 2018, 09:07

A couple of weeks ago I bought a 94 850 Turbo sedan. It had 120K miles (confirmed in the computer) and the body and interior are in real nice shape. Only a couple of small dents that are really hard to see and other then the tan carpet sun fading a little pink the interior is perfect with no rips. It does have a few issues that I'm working through to get to stage 0. I have already done the Timing Belt, tensioner, idler, and water pump. Car is running really good except for a few things. It has a lot of oil leak. I'm guessing that at some point the PCV system failed completely because it leaks from everywhere. Yes it leaks lightly from the front crank seal and a lot from the rear main. That's going to be a suck job but I will replace every seal and the complete PCV system and all of the vacuum hoses when I pull the engine. Right now it only barely inflates a glove but that could be because of all of the other places to release pressure through oil leaks

Now for the weird problem. I can't turn off the A/C. The A/C works great. Nice and cold and all of the controls seem to be working correctly inside. The temp knobs change the temp. The knob that adjusts where the air comes out of works and directs the air to the correct location and the A/C on and off button switches and lights the little light. But when I have all of the settings pointing to 0 the A/C compressor still cycles and cold air comes out of the vents unless I move the temp knob to hot. It is still really too cool to deal with A/C up here in Colorado it's only in the 50's and 60's at best right now so it's hard to do too much A/C testing.

I look forward to working on my Volvo and helping others as much as I can. Thanks for having a great site.

Post by **850 LPT** » 13 Apr 2018, 09:21

Welcome to the forum,

Looks like you found a good example of these fine Swedish cars

What color combo is it? Can you post some photos?

Sounds like you are on the right track with the PCV system, but you don't really have to pull the engine for that

. I have no clue what's going on with your A/C, but maybe your cycle switch is stuck?

Good luck with your 850 and many happy miles.
By the way, how many miles are on it?

Dirk

COS850Turbo · Post by **COS850Turbo** » 13 Apr 2018, 09:27

It is white with a tan interior. I'm not really looking forward to pulling the engine to replace the rear main seal but I look at it as an opportunity to seal everything up and give it a real good once over and fix everything that the last 20 some years has done to it.

Post by **matthew1** » 13 Apr 2018, 09:50

Welcome to MVS, COS850Turbo.

Post by **ZionXIX** » 13 Apr 2018, 10:08

Is there a fuse you can pull to disengage the magnetic A/C clutch?

Post by **scot850** » 13 Apr 2018, 12:04

Has anyone done a clutch repair on the AC compressor? One of the issues is if someone has tried to use the cable tie or bread clip repair but have over shimmed it so it can't dis-engage.

Had the car been sitting prior to you buying it?

To do the rear main you have to pull the trans, so if you do, you may want to replace the front trans seal (if an auto) while in ther as well as the axle seals.

What you could do is fit the PCV system and then replace the cam seals. Then try a bottle of ATP-205 in the engine oil and see if it helps seal the front and rear main seals once there is normal crankcase pressure.

Neil.

Post by **erikv11** » 13 Apr 2018, 13:36

scot850 wrote: ↑13 Apr 2018, 12:04 ....
To do the rear main you have to pull the trans, so if you do, you may want to replace the front trans seal (if an auto) while in ther as well as the axle seals.

What you could do is fit the PCV system and then replace the cam seals. Then try a bottle of ATP-205 in the engine oil and see if it helps seal the front and rear main seals once there is normal crankcase pressure.

Neil.

I like this approach, second that opinion.

For the AC i'm not sure what to suggest ...

Post by **mrbrian200** » 13 Apr 2018, 14:31

Sweet ride

COS850Turbo · Post by **COS850Turbo** » 13 Apr 2018, 17:07

Unfortunately the cam seals appear to be dry but there is oil dripping between the engine and the trans enough to leave a puddle on the ground. Unless there is something else that could be leaking above that location then I'm afraid that the rear main is it. Is it easier to pull the engine or trans in this car? I would plan on replacing all seals I can get to when I have the trans or engine out. Including the front pump seal and axle seals on the trans. I'm also toying with a 5 speed swap. Hey why not if I have to take it all apart any way

Post by **wizechatmgr** » 13 Apr 2018, 20:49

Is that one of the years where you drop it out the bottom after removing the sub frame?