leaking AC - where to start and end

[Clemens]

My 96 R is on it's original AC, except for a receiver drier 8 yrs ago and a zip ties shimmed clutch.
It would need a refill every 2nd year first, then every summer and now it won't even last a season. This is bad, because R134 is very pricey over here, and the ecological factor of losing freon is horrible.
Therefore I'd really like to fix that.

2 years ago when my AT went out I had to park my R for almost a year, and in that time the AC started to smell mouldy. A disinfection didn't help too much.

My indy diagnosed that there is dye around the compressor, which could be an indication that the compressor seals are worn, but not necessarily the only leak.

I never found any dye marks under the dash, but they might be hard to trace due to poor visibility

Should I start by replacing the compressor only, or bite the bullet and also do the evaporator under the dash?

My local indy, who specialices in old Porsches and Jags, recommends not to poor too much money into the AC because he claims that quite often, they still fail because only few people have the funds to buy every part of the AC system new - and in OE quality.

I hate the heat without an AC, but I also hate spending money and not getting a good r3sult out of the repair.

Any opinions or p80 related experiences are warmly welcome.

Thank you,
Clemens

[misha]

That's how my started to act...it was holding recharge for 3 years...than after few years i needed to service it every 2nd year....then yearly.
Last time it was holding for two months....recharged again and gas escaped over night.
Ac shop filled ac system with nitrogen on high pressure and diagnosed with bad evaporator.

Replaced it last year and it was a 3 days job.

Ac works like a charm but evaporator is freezing after about 1.5h on long journeys because compressor is not cycling in hot weather.

In the city...in stop & go traffic i don't have that problem because around town drives are about 30-45min max.

I need to go back to ac shop to check pressures because i think that system is overfilled.

New Nissens evaporator is smaller for one line of ribs than original and new drier is also a bit smaller than original.

System is refilled with proper amount of gas,but since new components are a bit smaller than original i guess that system now needs lower amount of gas by 15-20%.

Now...in cold weather...ac system is cycling properly because the pressure in ac system is lower in cold weather.

There are no leaks,low and high pressure sensors tested ok,cabin temp sensors for ecc are tested ok,new original blower fan.

I added a pollen filter with adapter from s,v70 to protect the new evaporator and blower from dirt since 850 originally came without it...and because of that evaporators go bad on these cars.

[scot850]

Also replace the Schraeder valve. These have a small o-ring that rots with time and leaks. At this age I'd replace it when you get the system recharged.

I agree with Misha on this that the likely culprit is the evaporator. If you pull the resistor pack out and use either a mirror on a stick and some light source you should be able to see the bottom of the evaporator. If it looks discolored or greasy looking it is likely leaking. Dash out job as you probably know but not terrible. A weekend would have it done.

I suggested to my Volvo mechanic buddy when I pull his dash to fix the mounts he might want to do this while it is in bits anyway. We will see nearer the time!

Good Luck!

Neil.

[abscate]

Im coming up on 10 years for my evaporator on Elizabeth , the 1999 T5 M56. That job led to me MVS, 11-12 years ago!

The original one died about 2011, so that was 12 years life on that.

[misha]

Mine was good untill two years ago.
So....it lasted for 25 years.
But...system was serviced regularly by professional ac shop.

[hausmeister]

AC on my 850 is similar, slow leak, worn clutch, and not working great.
I did take a peek at the evap, and it looks like something out of a horror movie. So needs to go, condenser also needs replacement, looks very worn. Need to replace the clutch at least. Dryer is rusted badly. Lots of work to do...

I do think a mostly complete rework is in order for any hope of reliable operation.

[abscate]

Getting the big nut off the dryer is almost impossible in those tight quarters. Solution: remove the suction line from the compressor, and then lift the dryer off with the hose attached. On the bench, the dryer hose is much easier.

I also cut the evaporator snouts off with a Dremel rather than fuss with the joints. Make sure you move at least 2.5 cm back so you don’t cut the hard lines.

Lots of good guides here

[scot850]

The evaporator connector can be a challenge as depending where you live, the wire coil ring that holds the joints together can become dirty or slightly crusty. Soaking with PB Blaster or similar for a few days prior to tackling separation attempts of the joints will help. I prefer this method as it gives a solid base to pull from to separate. Go with what works for you.

Good Luck! (especially with the drier nut Abscate mentions!).

Neil.

[Clemens]

I see a dash replacement in my future ... oh dear. I wonder if RobertDIY has a passport?