Topic: A/C Repair. Will later model R134A parts fit?

[2manytoys]

Need to repair my A/C before it gets too hot here in AZ. My original compressor is finally leaking and I have run out of my stash of R12.

The original owner had done the cheap R134A conversion a while back and it sucked so I put it back to R12.

Now that I have to buy a compressor and dryer anyway, I might as well do it right. Has anyone done an effective R134 conversion? Will it cool better with just the correct expansion valve or will I need to also get an evap and condenser too?

Can I take later model parts and put them on my 88 pickup?

[yotarunner85]

I don't know about later year parts fitting. But I have done many R-134 conversions with no problems. Done right it should be plenty cold. I have done several conversions using all R-12 parts and just changed the oil and freon to R134 by adding on the adapters you get from the auto parts store. I am A/C tech at a repair shop so it is easy for me because I have access to all the equipment to do the conversion. I have not done a 79 to 85 Toyota truck yet but plan to convert mine 85 4Runner soon. The last one I did was my friends 92 Camery last year and it's still working great.

[2manytoys [OP]]

Yotarunner, The last owner changed the oil and refrigerant and put the fitting adapters on the compressor. It cooled, but not very well in the AZ heat. The R12 is ice cold.

The adapters for the gauges were a pain because there isn't enough room to get the larger R134 gauge connecters on. Had to grind the case just to get one on.

I've done a ton of conversions myself on Cat equipment and it worked well, but we changed the drier, and expansion valve or orifice tube depending on the system.

Who knows what was done when mine was converted. Maybe too much oil or other problems. If nobody chimes in, I may just flush my system, get a compressor, drier, and expansion valve. It's all original stuff with 420K on it.

Thanks for your advice.

[yotarunner85]

Yea, if the system doesn't have the correct oil/freon levels it won't blow as cold as it could. R-12 is getting more exspensive and harder to find so getting R-134 to work maybe cheaper. Using components from a newer (1994 & up) that was designed for R134 may get colder, but don't know what it woud take to install them on an older truck.

[peacesells]

IMO 134a is garbage. Look into es12a, works excellent with toyota systems and only takes about 1/2 as much horsepower to compress. Toy compressors setup for r12 will fry with PAG oil, the 134a parts work ok with PAG. The main reason I wont use 134a is that you cannot run ester oil with it. Ester = quiet running long lasting compressors.

[yotarunner85]

Before anyone puts any type of Alternative Refrigerant in their vehicle do your own research and don't believe everything that people post about how amazing a product is. Also maybe illegal in some states. Here is a link to the EPA website for more info on Alternative Refrigerant.  http://www.epa.gov/ozone/snap/refrigerants/buying.html 

[2manytoys [OP]]

Well, I just went and bought a compressor and a dryer designed for R134 and an expansion valve for R134. I did have the option to get R12 specific parts.

I am running ester oil since the old system had mineral oil. That's what I was trained to use with the Cat retro fits and never had a problem. Most had GM or Sanden compressors. In new R134 systems we used PAG. Factory fill was PAG also.

Thanks for the link yotarunner. I'm aware of some of the "R12 Direct Replacements". I finally ran out of R12 and it's too risky to buy it now. You don't have a clue what is really in the bottle and I'm not buying a unit to test it.

I asked about the newer parts because I thought maybe the condenser or evap might be larger or more efficient. I'll update this post once I get it up and running. Thanks for the input guys.

[emsvitil]

Here's an AC forum

http://www.autoacforum.com/

[2manytoys [OP]]

Thanks emsvitil, found my oil capacity there. Lots of great info too.

The parts guy gave me the wrong compressor with the wrong fittings and 4 rib pulley. I should have made him cut the shrink wrap. Ahhhh!

Should have it up and running tomorrow........unless I go wheeling.

[2manytoys [OP]]

Got up early so I could get it done AND go wheeling.

System was really clean, no residue, but I flushed it anyway. Installed compressor, ester oil, dryer, and exp valve. Pulled a vacuum, checked for leaks, charged it up. Got icy cold with only one 12.5 oz can of R134.

Thanks for the input everybody. I really thought it wasn't going to be very cold.

[skin6061]

Im planning to redo my entire 1980 toyota ac's system with new r134 parts.  Glad to see this worked out so well.   I thought it might not be as cold either

[flyinsquirel]

134 systems use a different style condensor, which is why 134 doesn't work as well in an old R12 system.  Usually it will work fine while moving, but will not blow very cold when in stop and go traffic due to reduced air flow....according to what I've read.

I'm no expert on refrigerant/oil compatability, all I can say is that I'm running R12 in my 84 with a 3.4 and it works great.  That is with the compressor that came with the 3.4 which was originally meant to run 134, and the rest all stock components from the 84.  Can't remember what oil the shop put in it, but it's been two years and it still works great.

Good to hear it's working out for you.

[2manytoys [OP]]

squirrel,

I was thinking I was going to need a later model condenser or evap, but it's actually cold even when sitting still at an idle. The compressor is the same. I replaced mine because it leaked.

I'm surprised and very happy it worked out. It gets HOT here in Az. I usually don't run tha A/C when I'm wheelin, but I do when I'm headed to work or running around town.