Replacing AC Condenser

From a do-it-yourselfer...

Most systems do hold a little pressure, even though there is a leak and the refrigerant has been practically all lost. Sometimes it doesn't amount to a thimblefull of refrigerant. You are supposed to, of course, pull the remainder of the refrigerant out and capture it.

Be careful when removing and tightening the fittings. Some of those things are more delicate than they might appear.

When you take off the hoses, seal the ends (I sometimes use plastic and tape), to keep moisture and contamination out.

Use new o-rings or metallic seals everywhere you open the system. I use a lubricant/sealer like Nylog on the seals.

You may want to add 1-2 ounces of lubricant to replace any which will be trapped in the condenser . Be sure you use the right type for the system.

After you install the new condenser, you will need to pull a vacuum on the system for a couple of hours and then you can see if it will hold vacuum. (We used to pull a vacuum overnight on residual AC units which we had had to open. I dont think it is really necessary though, for this sort of application) If it doesnt hold vacuum, you will have to locate the other leak(s) and fix them. (You could also have a slow leak that is not easily detectable in this way. GM front compressor seals are prone to failure, at least on some models.)

When you are convinced that you are as leakfree as possible, then you can start to charge the unit. Since I only have a sorryass cheapo charge hose and gauge, I charge both by indicated pressure and weight of refrigerant. (I do have a pretty decent set of "scales" to weigh the refrigerant)

It is a lot more satisfying if you have the professional equipment which makes this sort of job easier. But if you dont,and are forced to do it for yourself, you can normally do a good enough job.

"Mike Y" wrote in news:q9l9i.193$ snipped-for-privacy@newsfe04.lga:

you can probably get your local radiator shop to fix any breach in a condensor tube for 20 bucks or so. unless you just want a new one.....if oil and refrigerant come in the same can dont worry about the trace amounts you may have lost......vac. the syatem for half an hour if you have a pump and manifold guage set, if not, buy an extra can of refrig. and put it in. then let it out (refrig. is hydroscopic and will gather most of the moisture) then fully recharge system...ive had this work great many o' time in driveway applications...............kjun

Thanks for the tips!

First off, I know where the big leak is. Pretty obvious, the condenser is 'dented in' and it's all oily and now has a lot of dye as well. One guy that looked at it said it looked like a bird met it's demise there.

I'm aware of the fragility of the connections. I have a set of flare nut wrenches, and I was expecting to have to use them. On my Pontiac I can only get at the condenser from the motor side, so that means take off the air box, then the fans, then the radiator... FINALLY getting to the condenser.

I was going to actually 'cork' the feeds, but it sounds from what you said that just protecting them is sufficient? That will be a lot easier to be able to just put say a sandwich bag and duct tape on the ends.

"Nylog"??? Never heard of it. I can't just use silicon? Or will that cause other issues? I'll see if I can get Nylog somewhere.

I don't think I have any other leaks. At least, there's no indication with the dye, so hopefully it will be OK.

I have an old refrigerator compressor and I was going to hook that up with an old charging hose to suck out the system. I have two charging hoses. One is 'direct' that has a can tap and a fitting. I was going to slice that to make my suction hose. The other charging hose I have also has a can tap, then a pressure gauge, then the attachment fitting. What's really weird about it is that the attachment fitting has to be 'pressed' to make it open the valve. It snaps on and seals, but it reads the 'can' pressure until you press on it. I don't know if it's defective or what, but it works and works well. I just have to press on the thing. Last time I charged, I just put a tie-wrap on it to hold it open to let it charge and didn't have to hold it.

For the oil, I was just going to suck the system out, then add cans that have oil and freon in them together. But are you implying that would be too much? My system says it takes 2lbs of R134a in the owners manual and that's about it. The oil and freon cans say

11oz so that would be 33oz, or pretty darn close to 2lbs.

The Chilton manual really sucks. It says absolutely NOTHING about the AC other than to refer to a qualified AC technician. I would never have thought Chilton was so bad until I saw it for myself.

Mike

You always wonder how much lubricant you may have lost. Probably not much, but an ounce or two should make it pretty close to right.

The filter/drier/accumulator used to have silica gel in it to take care of the water. If you pull vacuum long enough, you can return the system to near dry condition. This is why we pulled so long on residential systems. To be really sure, you can replace the filter/drier, but it might not be really necessary, especially when viewed in the light that you may not expect to get another

10 years out of this car.

By the way, Nylog is just one brand name for this type of product. I bought mine from

.. I think that there are other similar on the market. I would not use silicone on these seals. Either get the lubricant made for them or go with nothing at all. (Just my 2 cents.)

Thanks, but when I can get a new condenser for $101, why risk it. For $125 I can get a new condenser with a lifetime warrantee (except for impact damage). And I don't think I could get it fixed for $20 around here. What, about an hour of work? That would be $70 plus parts around here.

Thanks for the evac trick/tip! I may do that anyway unless I know my pump is pulling down to under maybe 10" of mercury.

Mike

Ok then... you're saying it would be better for a totally dry seal as opposed to wetting my finger with the AC oil and putting that on the seal.

Mike

Just make sure you get the right one. Had to replace mine in my 94, got it from autozone, wasn't even CLOSE to being the right part even though that's what their system said it was. Had to get it right from the dealer (and it ended up being cheaper to boot, go figure)

-GV

I've called around and the cheapest by far is the internet. ONE place said there's 2 different condensers for the car, but the rest just list one. Evidently one version comes with something different on the end, but they are the same when it comes to fittings, and either version will fit in my car. (Hopefully!)

Nope, I didnt say that. AC oil is okay. I would not use silicone.

The problem with the one from AZ was that it was WAY physically SMALLER than the one it was (attempting) to replace. There's no way it would have fit. Overall the job wasn't that bad, take out the cooling fans, remove radiator, remove condenser. That's all I really remember.

-GV

Was that the Arizona Air place? I thought they looked pretty good, but the prices there weren't. They were cheaper than the local discount places (those seem to run $180 or so). When you say smaller, you mean the mounts weren't the same? Or the fittings???

OK, one more question...

Turns out a place I found is local (less than 15 miles from me) offers a lifetime warrantee for non-physical damage, and while not the cheapest is way under the local discount places.

But, I see there are two types. Tube and fin and serpentine. Most places charge the same but a couple want a little more for serpentine. Also, the tube and fin condenser is specified as 'coupe' on a couple of sites on the web, while the serpentine is specified as coupe/sedan. But then, the dimensions seem the same.

What really is the difference? At least, from my point of view?

Another thing... Some of the places seem to carry 'generic' radiators. How much 'custom fit' is there going to be on most of these things if I don't get an OEM part?

Anyway, the place I found local is an outlet for Radiator Express. Any feedback on these guys?

Mike

What I meant by "AZ" was Auto Zone :) And what I mean by smaller is, lets just say, the condenser is supposed to be 3.5' long by 2.5' wide (not actual numbers just for this example) ... so then the one that autozone carries is 2.5' long by 1.5' wide, catch my drift? Does NOT match up in physical size at all. Like I mentioned, ended up getting it from the dealer, which was cheaper than autozone was, ironically enough.

-GV

Thanks!

I ended up getting mine from Silla. Well, one of the local reps for one of the internet companies that sells Silla. They had 2 in stock. When I picked it up, the guy told me they had over 20 in stock 2 weeks ago and they had a run on that model and the version that fits the Aztec (they had none of those left).

Anyway, it was $117. I know it was cheaper ($104) other places, but I didn't have to pay shipping, and I could get it immediately. They have a 'price match' policy, but then I'd have to have it shipped from the factory. Still, while not the cheapest, it was in the ballpark, and I could get it now. They had it waiting at the shipping dock when I pulled up to the warehouse. Can't beat service like that!

It was a PERFECT match. Well, not perfect. The cooling fins on the top are square and went right to the edge of the metal bracket. On the factory the cooling fins are 'tapered' on the top row. As a result, I had to trim the rubber mount slightly and even still it bent over a few fins at either end. No big deal. Oh, and it came pressurized to keep out moisture.

I didn't try AutoZone locally, but the two chain stores I did try were bumping $200.

I was gonna say but hit send too quick.

I put the condenser in last night. Went right in. Only now I have a bit of a coolant leak. I thing the lower radiator hose needs to reseat and I should move the clamp.

But... I went to evacuate the AC and my vacuum pump won't work. Damn, damn, damn. So I have to run to a shop today to get them to evacuate and charge the system. Oh well...

I looked at that Arizona web site and they sell a variety of vacuum pumps. And a nice manifold set. Maybe... If I get this new job... Only then I may just buy a new car and no more servicing AC! At least for a while.