Dryer or Expansion Valve Blockage ?

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Dryer or Expansion Valve Blockage ?

Postby JonnyWoodman » Thu Apr 20, 2017 4:44 pm

I acquired a 1989 Toyota Camry with just over 100K miles. The previous owner had a slow A/C refrigerant leak, but the A/C cooled well when recharged. Considering the age and low value of the car, he tried to use one of the leak sealers. The sealer didn't work of course. When I got the car, I injected die and found the leak on a hose coupling to the compressor, which I had a shop tighten, vacuum, and recharge. Now the system holds pressure, like 50 psi when equalized, but no cooling when running.

When the compressor is engaged, the high side goes way high, like 400+ psi I believe, and the low side goes down to near zero. So it looks like the compressor is working, but something is blocking the refrigerant. At first the shop assumed the expansion valve was clogged or stuck. So I had them replace it with a new expansion valve. Unfortunately, still the same symptoms.

So now my theory is that the leak sealer clogged the Dryer/Accumulator. Is that probable ?
My next step is to have the shop replace that. Does that sound like the right thing to do at this point ?
Any other things it could be ?
Any ideas or suggestions ?
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Re: Dryer or Expansion Valve Blockage ?

Postby Tom Greenleaf » Thu Apr 20, 2017 10:37 pm

Arggh! Sealer is generally (always really) a last try or you wreck a system IMO. Your call now how much you wish to go thru to get that out!

It would mean replacing anything the filters or has desiccant and a system flush then when all is good where it leaked too of course it's ready to charge probably using 134a converted so stick with 80% of the OE suggested amounts. I chose Ester for an oil for conversions.

Reasons it's plugged is sealer now IMO. You can see 400 PSI but it can't make the loop back near total blockage. The 50 PSI static if below 50F ambient temp about means the system is empty or it's just 55F degrees all around which is no time to work on A/C at all IMO.

Hey - Welcome to the site sorry that "sealers" never come with a warning that's it's really a last wild try or forget having A/C as it would cost quite a bit to clear that out and replace parts it's caught up in. OE condenser would flush if repayment now it wouldn't and have to be new again.

If you can handle it without A/C many would where I am in an older vehicle just avoid the hottest parts of days.

In short the cost now would likely exceed what you paid for this car so up to you if you invest tons or skip it. Reason to skip it is you still could do everything and find it not last for another reason and back to square one all over again - it gets nasty costly even if you do everything yourself,

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Tom Greenleaf
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Re: Dryer or Expansion Valve Blockage ?

Postby cornbinder89 » Fri Apr 21, 2017 8:20 pm

The bad news... well you already have it. The good news is it is so plugged, that finding the plug should be easier. I would take all the components that can be easily removed from under the hood ( I would leave the evaporator and/or the expansion valve if used). I would test and replace what fails to pass refrigerant (or air in a test). I would replace the hoses and try to clean the compressor. The problem is you'll never know if you have it fixed until have it back together and running for a while.
I have read, but have no real world experience, that sealers (or at least some) respond to moisture. In other words they are supposed to stay in an inert form until they encounter the moisture in the air, then set-up. I can see that if placed in a "wet" system.... well lets just say "concrete evidence" of a massive problem.
I have never had to rebuild a system after a sealer use, I have done systems that have been open for years, and suffered no real problems. The take-a-way from this, its better to leave a leaky system empty or open then place your hope in a sealer.
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Re: Dryer or Expansion Valve Blockage ?

Postby cornbinder89 » Fri Apr 21, 2017 8:26 pm

Oh, I forgot to mention, in the best situation, it is a crap shoot on if you are going to be successful. Since is isn't 100%, I don't think it is worth doing if you are paying a shop for labor and parts. If you are doing it yourself, and can pull the hoses and blow thru, same for the condenser and drier, your time and your skinned knuckles it MIGHT be worth a shot.
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