Hey folks, I've got a problem that has me baffled. I went through the entire A/C system on my 1988 DL. It was a new compressor, a new drier and a new expansion valve. When I removed the old expansion valve, it had a screen to catch little bits of junk but that screen was not dirty. I've flushed the evaporater, the condensor and all the hoses. I put all new o rings in and put in the PAG oil for the compressor. Even though the new compressor was BRAND new, I still had to change it over to use R-134A freon so I did that. I put the low compressor fitting from the conversion kit to the side of the compressor with the BIG hose that comes from the evaporator in the dash back to the compressor. This is the one that runs over the top of the valve cover. (yeah, you know the one.) Also, the R-134A conversion kit had like a little valve in it like is in a tire. The compressor had one also. To me it seemed silly to have two of those in a row so I pulled the one on the compressor out with a stem tool from a tire kit. Then I put the R-134A conversion it on. So it's like there is still a tire pressure valve in the hookup spot but only one and it's at the fitting for the R-134A adaptor.

I bought a vacumn pump and a set of guages from Harbor Freight. I hooked them all up with the blue hose going to the low pressure side, the red hose going to the high pressure side and I hooked the vacumn pump to the yellow hose in the middle of the manifold. I let it run for like an hour. Then I turned off the pump and let it sit for another 20 minutes to see if there were any leaks. The guages showed no leaks. So I closed the valves and disconnected the vacumn pump.

So finally I hooked the freon can to the yellow hose in the middle, started the car's engine, turned the A/C on full and poked the needle into the can. Then I backed the needle out a few turns to let the freon into the system and opened the valves on the manifold. The low pressure guage went way off scale and the high pressure side only showed about 10 lbs. ..... and no freon ever went into the system. And the guages didn't change.

I double checked everything. I made sure of all my connections. EVERYTHING. Still I get nothing.

What am I doing wrong?

 

was the compressor running when you tried to recharge it?

 

No it wasn't. It needs a certain amount of freon before the switch will activate and turn the compressor on. Also, I thought that maybe the switch in the dash might be bad and I jumpered the compressor straight to the battery but still nothing. I'm actually at a point where there is nothing left to trouble shoot. I mean, I've gone through the entire system and everything checks out good. But still, the compressor doesn't kick on.

 

Ok, here's an update.

I felt like maybe the connectors were bad, or at least I should not overlook ANYTHING. So I took the R-134A conversion kit back off of the compressor. Anyone familiar with this kit AND the 244DL can quickly see that there is a very tight fit between the R-134 fitting and the inner fender of the Volvo. I have to remove the air filter, mass air sensor and hoses to be able to even get to the fittings on the A/C compressor. Anywho, I took off the conversion and just used fittings for the original R-12. I figured that it wouldn't matter as long as I know in the future that the system is using R-134. Before I put the vacumn pump back on it, I put the little tire valve back in, hooked everything up and pulled a vacumn once again for about 45 minutes.

This time, the system started taking freon. I emptied three cans of freon into it but the compressor never did kick on. I can't find any leaks but I can't believe that I now have not overcharged the system. I don't know. I always find it interesting that, when I have some spooky problem that totally baffles me, it turns out that I really have multiple problems. Right now, I'm honestly thinking that the A/C compressor may not be grounded correctly. Therefore, the electrical circuit is open and, no matter how much freon is in there, it can't kick on. The compressor IS mounted on plastic bushings and I am beginning to think that I may have interupted a ground strap. A while back I remember the ground strap from the battery vibrating off and the bolt falling away while I was driving down the road. So I am wondering if I put it back in the correct place. I think that maybe that ground strap was mounted in a place what allowed electrical contact between the A/C/Power steering brackets and the engine block. I'll check that as soon as I get the chance.

However, time constraints prevent me from working on this anymore for about a month. I need to park the car and go out of town and I'll be back in June. So I'm really kind of bummed because I was hoping to have A/C for my 81 year old parents to drive while I was gone. They'll just have to share the ice cold A/C on their 940 that I repaired while I was working in this one. haha. If nothing else, I am learning a lot about A/C on Swedish Volvos. I've decided that one cannot expect great things from the A/C on a car that is built so close to the Arctic Circle. LOL But my success with the repair of the 940's system has encouraged me enough to let me know that I'm not TOTALLY incompetent.

 

did you pump a vacuum before adding the freon?

 

I did!

 

I believe you should have a low pressure switch on the receiver dryer. If so pull off the connector and jumper it and the compressor should turn on.

 

Ok, for anyone that was following this thread, I was out of the country for a little over a month. In the time that I was gone, the weather here has turned quite hot. I came back into town chomping at the bit to get this car's A/C working. I lifted up the hood and started visually inpsecting things. There is only one lead coming out of the A/C compressor of course, so I casually wondered if the system had a good ground on it. Obviously, with only one lead, the compressor must ground through the case. But the Volvo bracket is rubber isolated. So I crimped some "O" connectors on a piece of wire, hooked one end to a bolt on the compressor and the other to a good ground on the body of the car. Wham! The compressor kicked right on and I've been enjoying cool air since.

My only question now is how much freon should the system have? I put in three cans. I have a thermometer stuck in one of the dash vents and it never shows less than 60 degrees. My folks have a 940. When I put the thermometer in their car, the 940's system will take the thermometer right down to a little under 50 degrees. I'd like to tweak my 240's system for a little more output if possible.

Any suggestions?

 

the 240's AC sucked when new. the 700/900 have much better AC from the factory.

as far as how much freon, well, has the system been converted to R134, or did you put R12 in it? the onyl way to know the correct amount to charge is to evaculate it first, pump it down to a hard vacuum, leak test it, then charge it with the correct number of pounds. Can't say I know those numbers for a 240, we never fixed ours when it died young as it never worked that good new.