'93 a/c compressor in a '94 system?

[Mike Compton]

I have a 93 and a 94 ATX.
Looking to take the A/C compressor from the '93and put it in the '94.
My concern is that '93 had r12 and the '94 is r134a.
Is there any reason that i can not, or would not want to do this?

thanks.

 

[shojuan]

I think they are the same Nippondenso 10P15F compressor. In fact I just did a quick search to confirm, all V6 SHO's ATX and MTX use the same Nippondenso 10P15F compressor.

What I want to know is did the 94 and 95 SHO's have bigger condensors as well as any other parts to make up for the differences with 134A and can I use those parts on my 89?

 

[SHOtimer]

I personally wouldn't switch them but, if you want to you will need to have the '93 compressor chemically cleaned and prepped to go from a R12 to a R134a system. Besides being different refrigerant types, the systems have 2 different oil types and the O-rings are different. You could do it if you wanted to.

I also have my old compressor if you are interested (mods- I have a classified for that).

Rick, I'm pretty sure that the R134a systems do have a bigger condenser but i'm not positive. You should have remembered yesterday and we could have compared the two systems.

Doug

 

[drdave]

You don't have to have the condenser chemically treated, just use synthetic oil for the conversion. There won't be a problem with the two different oils. It is a good idea to change all of the o-rings though. But if your original compressor went south, beware of the dreaded "Black Death". If you have any king of black residue or black oil come out, plan on replacing everything except for the evaporator. And I do mean everything!

I think that condensers are the same. I could be wrong, but from past experience, I believe they have the same part number. But either way, the original condenser works just fine with a properly retrofitted AC system.

 

[SHOtimer]

I think he was asking about the compressor, not the condenser. I was suggesting that if you are going to swith a R12 compressor to a R134a system that it should probably be cleaned before hand. But, that is just my common sense and mediocre AC knowledge speaking... :burn_out:

Doug

 

[shojuan]

Actually you DON'T want to clean an old compressor. Just drain the oil. He can clean the other parts and install new o-rings, receiver/dryer, orifice and then pull a vacuum on the system. But I have heard time and time again to NOT clean an old compressor when doing a retrofit. Just use polyol ester oil instead of PAG. PAG and R12 mineral oil don't like each other. Polyol ester oil will get along and just draining the old compressor on its side with the lines disconnected will get most of the old stuff out anyways.

Other than that tidbit, which I gleaned from the archives, you probably know a lot more about the AC system than I do Doug! :thumbs_u:

ps. I didn't even think about comparing the AC systems. If the later 134A equipped V6 SHO's had bigger parts and they would fit a Gen I then it would make sense to upgrade to those if buying new AC parts for a Gen I wouldn't it. Not that I'm planning on replacing anything if I don't have to hahahahaha!

 

[SHOtimer]

Well, I've never dealt with a refrigerant change and I didn't even deal with my old compressor, just replaced it. So, I wasn't privy to that knowledge...but I am now .

So, your one of those if it's not broken (completely) don't fix it kinda guys eh Rick? :burn_out:

 

[rangerj]

The compressors are exactly the same, i.e. 10P15F Nippondenso. SHOJAUN is correct, drain the oil from the compressor, but DO NOT attempt to clean out the compressor. Use a synthetic oil made for retro-fitting.

The best way to do this job would be to replace the accumulator/dryer, the oriface line, and have the condenser cleaned and pressure tested. It is not a bad idea to clean the evaporator core but not 100% necessary unless a lot of black "crap" is found in the other parts.

If you do not replace the aforementioned parts, then assume there is 2 ounces of oil in the condenser, 1 ounce in the oriface line and an ounce in the accumulateor/dryer. Add 3.5 to 4 (no more than 4) ounces to the "new' compressor. Replace the "O" rings. Vacuum the system for no less than an hour at 27 to 30 inches of vacuum. rangerj

 

[shojuan]

Ranger, I am finally beginning to get all this AC business thanks to your continuous input on the topic! Really, now that I'm paying attention in *my* time of need I am truly thankful. As I'm sure the folks that you've helped in their times of need have been over the past MANY years! :thumbs_u: Do you happen to know the answer to my question about whether the 134A factory equipped V6 SHO's have bigger condensors and evaporators to compensate for 134A and whether those parts would fit a Gen I like mine?

 

[rangerj]

SHOJAUN,

The condenser used in the SHO from 1989 to January 2, 1991 is Motorcraft part # F4DZ19712AA, from 1/2/91 through 1995 is # F4DZ19712BB, and in 1996 # F6DZ19712A.

Is the difference "volume", or is it a mounting or hose placement difference?
The difference could be as simple as the placement of the overflow bottle attachment. If there is a difference in the overall surface area, in re. cooling air surface, I have never noticed a significant difference, but that does not mean that there is not a difference for the systems using R-134A.

The R-134A was used on vehicles produced after a prescribed date in 1993, for the most part 1994 models. The same condenser is used from 1/2/91 until the 1996 model year when a change occurs.

So, what is the difference between the two condensers used prior to 1996?
I do not know. I'm still looking for some detailed information about the condensers, particularly the "cooling area" and volume. If I find it I'll let you know.

That really is the question you are asking, i.e., would the R-134a be more efficient with a condenser that has more volume or a greater cooling surface, right?

Just as a side note, both R-12 and R-134A boil at temperatures below -200 degrees F. I would defy anyone to be able to tell which one boils off the fastest, that is which one is "more efficient". I know there is more to it than that, and there there are several steps in the A/C process that the two refrigerants respond differently to, but the difference in efficiency is very minor.

The key to a successful conversion is cleaning the system, replacing the accumulator/dryer and the oriface line, AND proper vacuuming and removal of moisture from inside the system. rangerj