Bill Ball

Right. I would not want to do anything more than top this one off with R-134a from a can. But all AC systems are an unknown unless you have owned the car from day one.

blown 87

I have lost 2 recovery machines due to sealant, almost ten grand worth.

No way to check for sealant that I know of, unless you know a way.

blown 87

Most good shops can, we test ever car unless we know it.

PatrickB

Thanks to everyone for your help!

Ed Scherer

Well, apparently you just hook them up to a recovery machine and see what happens... Or maybe you meant "no simple inexpensive way."

Seems like that sealant crap (like so many other patchwork solutions) costs everyone so much more money in the long run.

BTW, don't the recovery machines have filters (or recommend external in-line filter) that will catch the sealers before they screw up the rest of the machine? Just wondering, since I've got an external filter on my el-cheapo (compared to your stuff) Appion G5 Twin recovery machine. Or do sealers invariably make it through? Just wondering; I don't know much about this stuff.

blown 87

Sadly both of the machines I lost did not have filters that worked on them at the time, it seemed to get past them.

And no, I meant ANY way, even if it is not simple or cheap, just not as much as loosing another machine, which may have happened to a third one, it is throwing error codes as of yesterday.

Imo000

call and ask.

JHowell37

If it were mine, I'd start over from scratch. I'd take it apart, flush everything, replace o-rings, expansion valve, and drier. I'd fill it with the proper amount of oil, vacuum, and recharge it.

I would bet that your car was "retrofitted" when you told the dealer you'd only buy it with working A/C, and also because it was only 13 years old at the time.

A proper retrofit will take a lot longer than one or two hours and entails changing the drier and possibly the expansion valve. Unless it was a Porsche dealer, most shops aren't going to stock these items. I'd bet your car still has the original drier and expansion valve.

One thing to remember about most used car dealers is that they don't want to pay for ANYTHING. They don't even want to pay to have the car washed before they sell it. I would bet that whoever got your a/c working dumped in a few cans of one of those one-size-fits-all products that contains the sealant, dye, oil, and the propane/butane refrigerant. And your car just happened to be the one where the leak was small enough for the sealant **** to work. Your car even has the ****ty adapter caps (a clear sign of pinching every penny by the dealer.)

blown 87

It pretty much takes a full day to convert one back to R12, you would not think it would, but you pull the AC compressor, expansion valve, flush every thing, change the drier.
We are in the middle of doing one right now.

SeanR

If you don't know what is in there to start with, I'd say to do that and then just change it all over to 134. The longest part might be getting that damn expansion valve out of the earlier cars.

blown 87

We had just done a 134A fill on this car, then I took him for a ride in mine with R12.
I had told him there was a difference, but one ride was all it took.
both are 87's BTW, and my pump is a little weak, so his may end up cooling better.

It must be the humidity here, but 134A just does not do the job on a black 928 with front air only here.

I wish now I had put the rear ac in when I had the motor out, oh well I will do it at some point if we can ever get caught up on the cars out in the lot, we are running out of places to put them.

SeanR

I hear ya, until this past month I was convinced you couldn't get an R-12 system to cool as well with 134. I did two and couldn't believe how cool it got. I was really surprised. It also wasn't a cheap job.

I don't think there is anything you can do with a heat soaked dark 928 interior though. One of the reasons I put in classic gray and got rid of my dark blue dash/stuff. On the rear air, I almost never use mine, the kid has to be in the back for me to turn it on. Don't bother trying to install one in a car w/o it. Not worth the price or the pain in the *** to do it.

blown 87

Not understanding what you are saying in the first part, are you saying that you thought 134a would be as good as R12 before.
We are undoing a 134A conversion, putting back R12 in his car.


Everybody keeps telling me that about the rear air, I guess i am the COD cat, just bothers me that i have it there and it is not being used.

You have no idea how bad it bothers me that I have had that 5 speed on the floor as long as it has been sitting there.

SeanR

I was trying to say that I didn't think that a 134 conversion could be as good as 12. I kinda proved myself wrong.

On your last part, get off your *** and get to work son.

i can say that because i dont do it either

blown 87

If you saw a improvement by going to 134A then you have corrected a problem with the R12 system during the change over.


The biggest things are condenser size and humidity from what i have found, once the temps go past about 90 it goes south for 134A from a temp/pressure standpoint.

I did one back to back, r12 to 134a and then back to r12, full flush and drier change, that answered any questions I had.

In traffic around Atlanta on a 95 degree day in a black 928 with 134 is going to be not a lot of fun.

I can not explain why you got better results with 134A if all was equal.