So I am putting together a list of all the parts I want to replace for the a/c system in my 05 Tahoe with rear air. Right now there's a leak big enough to empty out in less than a couple days but even with dye in the system I can't find where its leaking from. So because of that and age/miles (220k), I just want to replace everything. Already know plan on everything under the hood and the conversion to rubber lines to the rear, but what about the rear area in the rear where those lines go into? Are there common leak areas in that box? Anything serviceable?
A/C Rebuild Question(s)
- Thread starter Noggles
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Donal
Full Access Member
The mechanical seal in the compressor is the common high wear item in the system. I f you have checked all connections with soapy water and rag and fpound no bubbles, the seal is a likely leak point. If you are going to replace "everything," anyway, start with the compressor, drier/accumulator, evacuate the system a bit and recharge. Remember the compressor seal is not rated for deep vacuum, just high pressure. You can use a venturi device to get the vacuum down to around 10 to 12 inches of mercury and be good.
You have a specialized question and need some patience to allow for other members to respond.
I am hoping the leak is the compressor. My plan is to replace all the parts myself since the system is empty anyway and then take it and have it professionally refilled. My fear is the pieces I am not replacing (like the stuff in the rear) has some sort of debris in it. Is there some way to clean that out before I put the new pieces on?
swathdiver
Full Access Member
There are inline filters to catch that debris. I've got a mystery leak too, started while the truck was sitting and even with sniffer we still cannot find it. Going to let the dealer find it then will decide on who gets to fix it.
bill1013
Full Access Member
I don't know the condition of your unit, but if you're going to tear it apart that's up to you. i would find the leak before I did anything else. You may rebuild it and still not find the leak. It's been my experience that A/C Units don't need overhauls when properly maintained. But again, you have it in front of you and you know it's condition, if not the history of the vehicle.
I had a 1984 Ford Bronco II 4X4 V8 2.8L that had a similar problem to yours except mine leaked out within an hour. Took it out and pressure checked it on the bench and there where leaks everywhere. Even the compressor body had small, pin holes in it. Probably from corrosion. So I scrapped it and ran without it until I found a suitable replacement at a good price. The replacement was a lot bigger, but I got it in there and man did it get cold! Even on Low the wife, now ex-wife, complained about it being too cold. I just told her to ditch the shorts and wear long pants. Yeah, she didn't like that...but she didn't like it when I ran without A/C either. Sometimes you just can't please them!
I had a 1984 Ford Bronco II 4X4 V8 2.8L that had a similar problem to yours except mine leaked out within an hour. Took it out and pressure checked it on the bench and there where leaks everywhere. Even the compressor body had small, pin holes in it. Probably from corrosion. So I scrapped it and ran without it until I found a suitable replacement at a good price. The replacement was a lot bigger, but I got it in there and man did it get cold! Even on Low the wife, now ex-wife, complained about it being too cold. I just told her to ditch the shorts and wear long pants. Yeah, she didn't like that...but she didn't like it when I ran without A/C either. Sometimes you just can't please them!
My parents had to replace the engine bay components in their 01 Yukon many years ago and the person they had do the work for some reason had to redo the job a couple times because debris kept messing up the compressor or something. He also was replacing the filter as well. That part has me concerned.
I had it refilled and they filled it with the leak dye. I looked over as much of the system as I could see with a pair of orange glasses and an IR flashlight. The only place I saw some dye was the pressure port where it was filled. They said they also replaced the valve or whatever its called in that port so that was new. Even got a pen camera to look inside the box in the dash that I guess also develops leaks and didn't see anything in there either.
bill1013
Full Access Member
I would get the Illustrated Parts Breakdown for your unit and look it over for possible internal leaks. If the unit hasn't been maintained or serviced on a regular basis the internal seals & "O" rings dry out, get hard & develop cracks, which are small at first, but eventually blow out. You may just need to replace the Packing Kit or seals & "O" rings. Since you have a pen camera you may want to look for small cracks in joints, welds and "O" ring seats. It sounds like the carcass is good, no pin hole leaks or distortions. If you feel confident about tearing it apart and changing the seals & "O" rings then go for it. You could also get a certified A/C repairman to do the job. They have the special tools and are familiar with the problems that certian A/C units commonly have. Also, if you end up doing it yourself don't forget to lube, or condition, the seals & "O" rings before you put them in. I used a light coating of silicone de-electric grease worked between my fingers. I wiped off the excess on the rings after they were on. The grease helps keep the rubber supple. Adds a little bit of life to the ring. Good Luck!!
