Well, as someone else recently pointed out on the Opinions forum, summer is just around the corner. That means camping, fishing, and hunting, but not necessarily in that order. Also means that I need to find a way to resurrect my long-dead A/C.

I understand that Volvo changed to a rotary-style compressor in '86. I need to replace my existing compressor anyway (seized), so I figure that I might as well use one from an >'86. Is this feasible? Would I need the mounting bracket as well? Are there other options? How about a compressor from a Diesel? Or one from a large mid-80s GM sedan? Am I wrong to assume that the "bigger is better" principle applies here?

I've heard conflicting opinions about converting to r134a. A few indy. mechanics have told me that converting older Volvos is a waste of money because they will never blow as cold as they did with the original r12 setup. Others have said the cars that they have converted easily outperform any stock r12 system. R134a is also considerably more economical than r12 and I could (legally) charge my own system if I go this route. So, what's the "straight skinny"?

I've also been told that later model 240s have an electric fan on the condenser. Can one of these be retrofitted to my car? Appreciable gains for the effort?

Welcome any and all suggestions and feedback.

Thanks in advance.

-=Bob=-

Yes, you could convert to a later A/C compressor (post 86). They fit.

Look for compressors that have the letters "DK" in the model number on top. I like those because they aren't the Sanden ones that have to have the compressor seal changed if you convert to R134.

Then convert to 134. Add the condenser fan. Change O-rings, receiver dryer and expansion valve. Vacuum the system out and hold it to make sure it isn't leaking.

Then charge up the system. You should see very decent cooling with a 134 conversion. The problem with 134a conversions is that a lot--perhaps a majority--are either incomplete, or improperly charged.

Add the EXACT amount that the system requires, not in R12 figures, but in 134a. If you buy the Volvo kit, it says what the figures are. You can increase cooling by getting a light color dash cover (dashmat). The dashboard is like a heat machine in the summer sun.
--
Chris Herbst
1992 745, 68k

And others:
93 944, 150k
90 245, 110k
88 744, 160k
87 245, 185k

Hey bob - I'm not sure if it uses the same compressor but I have a brand new York Compressor (The big boxy S.O.B.) I purchased it as part of my planned rebuild but never felt like cracking open the A/C system. So it's un-used. Purchased from Sweedish Engineering about 8 months ago.

Jeff

I went to a wrecking yard monday looking for fans to use in front of the condensor. I found that the BMWs and the Mercedes 240 are the perfect size for the Volvo. They also have good mounting brackets that could be modified easily to fit the Volvo.

You can also get the fans off Mercedes 380, 420, 560 sel which are larger, but would still fit in the bay.

I found 5 or 6 fans within 15 minutes and they wanted $15 for anyone of them.

An electric fan mounted to the front of the condensor can be retrofitted to your car very easily. They are common in salvage yards around me. The 740 style does not appear to fit easily (mounted dead center on the condensor), but I've never tried. I pulled a fan from a late 70's 260 for my 81 242, as I recall its a 10-12" Bosch unit, mounts via two metal brackets to the vertial support post the horns are mounted to, and to the bit of sheet metal just behind the bumper. So the fan itself is covering the left half of the condensor (from front of car). I suppose if you really wanted you could fit two of them, one on each side, but it would block a ton of air. Wiring is simple, I wired it to a dash switch as my AC is dead (no R12 charge and no cash), but as another poster said, use an inline diode, and wire it to come on when the AC clutch engages. Very late 240's, maybe only the 93 (which should be a r134a system), had a pressure switch somewhere in the AC system that activated the fan, I think. You might look into that if you find one.
AC system improvement? No idea, it's as broken now as it was when I put the fan on. But that little fan does push a good bit of air, helps cooling at idle after high boost=high heat.
Good luck. I learned a lot from this thread, maybe I'll attempt to fix my AC this summer.

Logan
--
1981 242GLTurbo 1968 122S Automatic (Summer Project)

Are you sure you don't already have a rotary?
My '85 245 does.

If you use R134a, one of the variable orifice valves will help a little. I think there is something about this in the FAQ and definitely in old threads here. You might also find it by searching for AC and VOV or something like that. I paid about $24 for mine.

An electric fan, whether a primary one that replaces the mechanical puller fan or a secondary pusher one, that is triggered by the AC compressor definitely helps the AC in city driving. You need to use a one way diode in the trigger wire so that the AC does not come on whenever the fan comes on. I use a relay to set this up on my car.

Working with R12 is expensive now. It is best to find a substitute that is safe or use R134a. A few leaks with R12 and you have spent a lot of money.

Philip Bradley

A VOV is cannot be used in a 1985 240. 200 series older than 1991 do not use an oriface valve. 1991 and newer 240s can use a VOV, the system was redesigned for 1991, and it works much better.

If salvaging parts like a new compressor, could newer parts that take the VOV be salvaged as well, or would this involve the dreaded take apart the dash operation and is thus not worthwhile?

Philip Bradley

It's probably doable. BUT...you would need ALL of the A/C parts from a '91 or newer 240. I'm not sure how much work it would be to change the evaporator. The systems are completely of a completely different design. For '91 and up, Volvo switched to the accumulator/oriface valve type system. Older 240s have the receiver-dryer/expansion valve type system. Besides the compressor and condensor, I don't think any other parts are interchangeable.

Read the Hayne's Heat and A/C Techbook for a good general description of the different A/C systems.

-Ron

Literature on r-12 vs r-134 says that the r-134 has less cooling capacity than r-12, but I have not been able to tell any difference between the two. I have used a thermometer at the vents and can see no change. Customers have given me feedback over the years (we have performed about 100 conversions) and have said they detect no difference.

An alternative for you is Freeze-12 which is r-12 equavalent. It is about the same cost as R-134.

Two of my best AC resurrections are the '79 242GT and '85 244Ti "iceboxes" done with:
new expansion valve
Freeze-12
rotary compressor from salvage (shiny, new-looking)

to mount the rotary you need:
low side hose from 86-on (you need a straight end)
big mounting bracket off 86-on 240s only
power steering pump, hoses and mount off 86-on (for a turbo you need '90-on ps)

total cost was about $100 including PNP parts and they are very comfortably cold.

"rotary compressor from salvage (shiny, new-looking)"

I know very little about AC systems, but how do you go about pulling a compressor from a salvage car? What I mean is, does the system need to be drained before removing the compressor?
--
Volvo 240 Links | Parts For Sale | Volvo 240 Racing

The beauty of that is, if the car had R12 to begin with, and the towing company didn't get to it first, then the salvage yard already sucked it out!

But it doesn't hurt to stick a tip of a knife in the fill port, to see if it releases a lot of pressure. A little is normal; a lot is a charged system. I've had a face full of refrigerant and oil before... it's not fun.
--
Chris Herbst
1992 745, 68k

And others:
93 944, 150k
90 245, 110k
88 744, 160k
87 245, 185k

Well, it is encouraging from a functional point of view if the system has pressure. Maybe bad for the environment but good for the user. It means the unit is probably good and free of moisture. However, if the yard guys are doing their job, they should evacuate and recover the freon.
What I do is remove the compressors that look very recent using a 21 mm and 24 mm (sizes from memory, not for sure) box end on the hose fittings. At that point, escaping refrigerant is a done deal. I have had great luck with used compressors so far. 3 for 3. The rest, after teh two hose fittings, is the mounts, all 12 and 13 mm bolts. When you have the unit out, plug the holes to keep moisture and dirt out.

.
--
Volvo 240 Links | Parts For Sale | Volvo 240 Racing

what's the deal with freeze-12? do any changes have to be made, or can it just be put right in to the existing r12 system? (i.e is it easier than doing the r134 conversion?)

No changes other than mixing a little oil (as I recall they recommend a dab of ester on top of the standard oil). Freeze 12 is said to be mostly R134 anyway, but I have just seemed had better luck (colder refrig) with it. I use R12 gauges and fittings with it. R134 is nothing harder except for adding the fittings and having R134a gauges too. If you have gauges and a vacuum pump you will never need a shop (ie huge AC budget) again.

what kind of vaccum pump (and cost to purchase ??) are you talking about so that "you will never
need a shop (ie huge AC budget) again.". I assume you need it to run a vaccum on the system for like 50 minutes?

I figure I can just kind the gauges from walmart or something.

thanks
zakir

You can make your own vacuum pump.

Go to the wrecking yard and get an old York compressor or an old Chrysler compressor. Build a mounting frame(on wheels is best) and hook up a 1 1/2 hp electric motor by fanbelt to the compressor. Simply make a hose that attaches to the suction side of the compressor and attach a fitting to connect to a cars a/c compressor. It will pull about 27 inches of vacuum which is all you are going to get out of a a/c system anyway.

I bet you could make the whole thing for less than $30 if you all ready have an old washing machine motor or something in the garage.

It takes about 10 min to pull a good vacuum

thanks for that info !