Complete AC system overhaul

[eurasiaoverland]

Hi guys

I'm heading off to potentially hot places in my 3rd Gen next year, so next job is to reinstall the AC system.

When I got the car, the system was de-pressurised and the condenser was falling apart, so I just took everything out, carefully covered the ports to the expansion valve / evaporator and put the parts in storage.

In preparation I have:

-new dryer
-new condenser
-all new clamps etc to hold everything together
-all new O rings for the system

I am going to use my original pump as the remanufactured units seem to be of very variable quality and I don't want to shell out for a new one. I know the new Denso units are not very expensive, but I guess they are made in China (like the new condenser ) and not as good quality as the original. I also hate to throw good parts away and I have no reason to think there's anything wrong with the compressor.

I'm going to re-seal the compressor myself as it's 22 years old and has been sitting without refrigerant in it for who-knows how long. It will also let me visually check the internals for major wear or damage. There's a great video here to show how to do it. I have a genuine Toyota seal kit and a genuine Toyota shaft seal ($59! ).

That only leaves the evaporator and expansion valve. I plan to remove these to give them a look over and clean any dust, fluff or mold off.

For the evaporator I cannot imagine that it would be defective providing there is no visual damage to the unit.

What about the evaporator valve though; do they wear out? I'm happy to replace it if they routinely go, but if they are simple, last-forever mechanical valves then I will leave it be. Will still change the O rings though

Any advice welcome, this is the first time I've done anything with an AC system.

Thanks

EO

 

[TheDurk]

The evaporators are a trouble-prone part after 20 years. They sit there in the dark, frequently wet, and they corrode. I have seen some pretty depressing pics of old evaporators as mold gets going. I have a slow leak in mine that I will attend to once my current charge leaks down. I have seals, valve and evaporator ready to go. My thinking is once I got to the effort of getting that thing out of there, I want all new pressurized parts on that side of the firewall. The valves do go bad, although not all that frequently.

 

[eurasiaoverland]

Thanks Durk. I like your thinking. I will take a look at the evaporator from the outside and if there are any signs of corrosion whatsoever it will get replaced

Again, as I'm RHD my evaporator is a different part to yours and is no longer available from Toyota, leaving me with used original or new Chinese crap as an alternative. Maybe I can take it to a local radiator shop to get pressure tested, though I'd be worried about moisture getting inside.

 

[96RedRunner]

Don't worry about the moisture, when you close system up and pull the 30" of vacuum that will get the moisture out.

 

[Kennysmoke]

My compressor seized up on my '98 and was getting ready to order a new Denso comp, valve, and drier from RockAuto. My condenser looks mint on the outside... should I replace it as well?

 

[JayRolla]

My ac compressor just took a poop. Making some horrible sounds. Sucks oems cost so much. Almost rather find a low mileage used one.

Are the compressors the same between all years?

 

[eurasiaoverland]

My compressor seized up on my '98 and was getting ready to order a new Denso comp, valve, and drier from RockAuto. My condenser looks mint on the outside... should I replace it as well?

Yes. Chances are it put out metal debris when it seized, straight into the condenser, which will stay in the AC circuit if you don't change the condenser. This may affect how well the system works (due to obstruction), fill your new dryer with crap, block your expansion valve, and perhaps even wreck your new compressor.

 

[eurasiaoverland]

My ac compressor just took a poop. Making some horrible sounds. Sucks oems cost so much. Almost rather find a low mileage used one.

Are the compressors the same between all years?

I believe they're the same on all 3rd Gens. Denso PA-17. But please check with part numbers. My (1996 JDM) is 88320-35450 which is the same as on a US market 3RZ 3rd Gen of the same age. The V6s have a different part number, though I'm pretty sure the only difference is the removable valve head on the compressor, which may not be supplied on a remanufacture or non genuine unit.