'93 conversion questions - hoses, compressor, etc.

[Anime]

It's become apparent with the fitting leaks that the original system has shot o-rings, and it seems more worth my while to convert to easily-available R-134a, finally making the A/C system a DIY item rather than seek out rusty old cans of R-12 or paying hundreds of dollars to get ripped off at the local A/C shops.

I'd like to swap out both the longer discharge and suction line and the shorter liquid line to barrier-type hoses (with a R134a fitting on the suction line rather than an adapter fitting), and the receiver/drier and switch to one with an R134a fitting as well.

NAPA apparently has an R-134a discharge/suction line, but I've yet to actually see it to tell if it has the R134a fittings or not. Their online catalog just shows the same R-12 hoses from Four Seasons/Spectra that you can get everywhere else.

Anyone had any luck finding a pre-made set of R-134a barrier-type hoses for the 93-94? Do they just make R-134a discharge/suction hoses and the liquid line for the R-12 system works fine? Are R134a receiver/driers available or you just have to use the adapter fittings?



Finally, I haven't decided on whether or not to replace the compressor. Mine hasn't had any problems, and I assume despite the R-12 leaks, there's been enough oil to keep it lubricated.

However, the possible casing/housing leaks in the middle have me wondering if the o-rings are shot and I'd be better off with a new one while going to the trouble of converting the system. I know the rear leaks are just from the bad o-rings on the discharge/suction line. I assume it's more hassle than it's worth to rebuild the FS-10 compressor, rather than buy another?

 

[Anime]

bumping since people are replying to posts in the A/C forum now...

 

[Anime]

bumping since the A/C forum is active once again...

 

[Glacier991]

First off, you can get custom hoses made. I can give you the phone and address of a place near me in Sacramento that could take your old R-12 hoses and duplicate them using barrier hose. There may be places that sell them premade, but I cannot point you to any offhand.

There is nothing wrong with re-using the compressor, but depending on the age etc, it will have to work harder with R-134 and might not be a bad to replace it. Make sure you use green O-rings and Nylog in your assembly.

If for any reason you cannot find or buy a barrier hose you can always flush out the hose with mineral oil. There is some evidence it acts (somewhat) as a barrier and improves the barrier-like perfromance of non-barrier hoses. How well or for how long I cannot say.

You might also consider adding a fan in front of the condensor... that is the weak link in a conversion heat-disipation wise. Also an overpressure cutoff is not a bad idea on the high side.

Glacier

 

[TheJackal]

My old 89 Vic had a R-134a retrofit.

When done right, it performs well enough that the efficiency difference is not a concern.

 

[Anime]

Further research shows the compressor is a FX-15, and therefore not good for the pressures of R134a. I will be replacing it with an FS-10.

It also seems that all the hoses you can buy at the parts store from the same manufactuer under the Four Seasons/Factory Air/etc. brand names are indeed barrier hoses compatible with both R12 and R134a, even though the hoses for 1993 and earlier applications still have R12 fittings which will require adapters for conversion.