A/C System Repairs – 1989 Cadillac Deville
Mark: Hi, it's Mark Bossert, producer of the Pawlik Automotive Podcast. We're here in Vancouver of course with Mr. Bernie Pawlik and they've just announced we're 20 time winners of Best Auto Repair in Vancouver as voted by other customers, and we're talking cars, how you doing this morning Bernie?
Bernie: Doing well and happy to have one the Best of Vancouver again, it's exciting news.
Mark: So here we go. We're talking about a 1989 Cadillac Deville, which is a pretty old vehicle but still the AC system had some issues and that's pretty relevant to all cars, what was going on with this Cadillac?
Bernie: So this Cadillac came to us, the owner really liked their air conditioner working properly, I mean it's one of the nice features of the Cadillac, in fact every car has air conditioning now so, they used to be kind of a unique Caddy feature but very important to the owner of this car and she'd had it repaired several times in the past and it still wasn't working properly, so we took a look at it, did some diagnostic and testing and found some interesting issues that I wanted to share.
Mark: So, with testing and diagnosis, what did you find?
Bernie: Well I mean, first issue we found was the refrigerant was quite low. We did a visual inspection for leaks, which we normally do, didn't find anything. Added some refrigerant, went to test the system and it was interesting because the compressor would switch on for a couple seconds, would generate some pressure and then switch off and it wouldn't run anymore unless we shut the key off, recycled it. We did the whole key start cycle and then it would run for a second or two and then go, so I mean, we figured we had a leak somewhere so we did a thorough leak test, couldn't find anything, so obviously whatever was leaking was pretty minimal.
We looked over the system electronically and weren't sure where there was an electronic problem or what it was, but finally realized that looking at the system pressures when starting up, the air conditioning systems have a high and low side pressure, and what would happen is we start the vehicle up and the compressor would kick in and we could manually kick the compressor in and even with a full charge of refrigerant, the low side went into a suction, like into a negative pressure, into vacuum, which is incorrect and then the high side pressure would not generate much pressure also, so we figured there was probably a blockage in the system somewhere so we kind of dug a little further and found some interesting pieces. A little bit of history, the compressor had failed on this vehicle once and the person I guess had not put oil in it and that caused the compressor to fail, so someone had put another one in, properly oiled the system, charged it and then it stopped working after a little bit and arrived at our shop. So there was some repair history to the vehicle and so, there we are.
Mark: So do you have some pictures?
Bernie: I do. I have some awesome pictures to share.
So what we have, this is an Orifice Tube, now this actually the item that we found was plugged. What we found was when the compressor had failed at least once or twice, or sometime in the process of repair, someone should have looked a little closer at the Orifice Tube and flushed the AC system. The reason I'm showing the new part is you can see this is basically a screen with a little small ... It's basically an Orifice, it's a small opening and as the liquid moves through here, it changes the pressure or changes the state, I'm not going to explain this correctly, but there's a state change from liquid to gas or gas to liquid and that's what causes it to generate cold air. What we found was this, this is, if you can even make sense of it, this is the Orifice Tube we took out of the vehicle.
All this black stuff, this is dirt debris and crap from a failed compressor that's basically just covered the Orifice Tube screen. I'll go back to the other picture because it gives you kind of an idea, that's a good one, that's the bad one. This thing was completely plugged, so when the compressor was generating pressure, of course it was trying to force the liquid through here, it wouldn't go anywhere and it couldn't suck anything because the liquid and gas wouldn't circulate through the system, that's the key with air conditioning, it's a circulation system. So a couple of other things were the Orifice Tube bolts into the evaporating core pipes, this is the fitting here and you can see, not so clearly but there's a lot of dark, gray debris in here, and one of the repairs we did, we'll talk about this in a minute was we flushed the system out and well, this is a bucket with a bunch of very, very black liquid in it, so those were the pictures I wanted to share with you.
Mark: So how does this much contaminant get into the AC system? Isn't a close system? Sealed?
Bernie: It is a closed and sealed system and how the contaminant gets in is basically as the compressor fails, there's components in the compressor or if it overheats, there's oil in the system that gets damaged. So once we figured everything out, it all kind of made sense. A compressor failure, someone didn't flush the system and that's basically what caused everything to block up, so the proper repair is to basically take things a part and flush it out. Now, we obviously replaced the compressor because that was damaged, there's also the accumulator in the system, sometimes it's a receiver dryer but there's slightly different operation components but that's the filter of the system.
That component we replace, we obviously replace the Orifice Tube because it was completely useless but everything else, we flushed all the lines and pipes out. We flushed the evaporator, we flushed the condenser. It's a nasty job, it requires extremely expensive special chemicals, and we basically blow these chemicals through the system and do it until it actually comes out clean. That debris you saw in the bucket, that's sort of the first round of flushing but we do it until everything comes out spotlessly clean and that removes all the debris.
Mark: And how did the AC work once you got everything back together?
Bernie: It was fantastic. It worked really well. Nice cold air, compressor cycled on and off just like it should, all the system pressures were normal and worked really well.
Mark: So since this is such an older vehicle, how have AC systems evolved over the years?
Bernie: Well, they've evolved in a few ways. One of them is a lot of the components are smaller, like the compressors, if you look on a 1970s car were massive. Some of them were almost ten inches long, circular compressor, which was what was on this Cadillac or some of them actually look like a little V engine. Chrysler's had those they're like a two piston V motor, it's kind of a cool looking piece but they've evolved down to quite small, I'm thinking some Subaru's for example, the compressors on those are only like about four or five inches deep and very small and they accomplish the same thing. I mean that's one thing, the components are smaller, the refrigerants have changed. Air conditioning used to use R12, which is an ozone depleting refrigerant, fortunately we stopped using that and gone through R134A, which doesn't deplete ozone but still creates global warming when it's released, it's a global warming chemical.
There's now a new refrigerant R1234A, which has been used on in the last few years on some cars, very expensive refrigerant, it doesn't deplete the ozone or cause global warming, so that's a good thing but I've heard word that maybe that refrigerant's going to be changed to something else, so who knows but that's kind of the most modern iteration. But that's really how air conditioning has changed, either than that, the system operation is pretty much the same whether you're talking from a Tesla to a 1962 Cadillac, it's all pretty much the same it's just with a Tesla and a lot of hybrids will be an electric driven compression not belt driven like you'll find on most other engines.
Mark: So this is a bit of a well aged, well loved vehicle, is it worth fixing?
Bernie: Well, the owner of this vehicle loves it, so she likes fixing. I'd say beauty is in the eye of the beholder, it's like people have attachments to cars and so, if it's worth it to you, then it's worth it to you, you know. But there are cars were we will tell people, "We don't think you should spend your money on this vehicle," and sadly I see a lot of people who don't spend money on cars that are well worth fixing that don't but everyone has their opinion. The owner loves this car, so that's why we fixed.
Mark: So there you go. If you're in Vancouver and needing AC repairs the guys to see are Pawlik Automotive, you can reach them at 604-327-7112 to book your appointment, or check out the website, pawlikautomotive.com. YouTube channel, Pawlik Auto Repair, hundreds of videos on there. As well, thank you for listening to the podcast and always remember we're in Vancouver, we don't provide technical support over the phone or by text, which I just got one. We're in Vancouver and we provide in person service because that's the only credible way to actually provide service for you and thank you Bernie.
Bernie: Thank you Mark and thank you for mentioning that. Thanks for watching, we really appreciate.