Quick A/C filling question

[djnolan]

Should I start a new thread or just hijack this one?

I have an 85.5 944 with bad compressor o-ring seals and a lot of oil leaked out. I have a seal kit and a new receiver dryer. I was planning for Freeze12 refrigerant. I will replace any disturbed o-rings. How much oil should I add? Seems like all oil in the compressor leaked out. I can only assume the sytem has what is left of the original oil type in it. I would like to make this a permanent repair so going to a little extra trouble flushing and re-oiling etc wouldn't bother me but if I can just put in a few ounces of oil X instead...

thanks!

[kuehl]

replacing drier and compressor on a 944, use 6 ounces , you could go as high as 8

[John_AZ]

Info on Freeze 12:

If you take your Freeze 12 converted car to a shop for an AC repair you cannot fix, they may not work on it.

eBay Guides - Freeze-12 Refrigerant R134a

John

[mattdavis11]

It depends, if the front seal went fast, then be liberal with the mineral oil during assembly after cleaning all the parts. Coat the new seals well too. You can run through an 8 oz. bottle when you knock it over.

These compressors weren't sent to Germany dry. They probably were full, but assembly capacity prior to testing was probably 1-1.5 oz, then they added more later. Take a close look at the shaft where the seal rides, it has to be smooth, if you can't get it there with 220, it's gone. I'd recommend adding 2-3 ounces following assembly, but I know nothing of the amount lost. It's a judgment call. How did the compressor look after failure?

I stay away from Freeze 12, but people have had good luck. YYMV.

I'd invest in a low side R12 to 134 elbow fitting, rebuild with pag 46 and charge to around 27-29 ounces of R-134a. While you are taking the time, it would be wise to clean the condenser. What ever means it takes, but don't use a pressure washer.

The best way is to remove the radiator first.

[kuehl]

Originally Posted by John_AZ

Info on Freeze 12:

If you take your Freeze 12 converted car to a shop for an AC repair you cannot fix, they may not work on it.


John

The issue is cross contamination: most approved alternative refrigerants, something other than R12, use different service port adapters and refrigerant identification labels, reference here:
MVAC Refrigerants Fitting Sizes & Label Colors | Alternatives / SNAP | US EPA

You'd be surprised as to how many people (DIY and service techs), "unknowingly" of the potential outcome, forget to put a label on the car or swap service port adapters.

A service tech could unknowingly recover the unknown refrigerant into their R12 machine and that would contaminate their refrigerant recovery bottle..... meaning they would end up with mixed gas which is a NO NO in technical terms as well as EPA regulations. Most tech's don't have refrigerant identification equipment. Yeah, if I was the tech I'd be pissed for sure.

[mattdavis11]

That's a good point. If you do the work yourself and decide to sell, label it. I've left the high side fitting alone, it's still R12. It doesn't matter to me because I have both sets of gauges. I consider it an insurance policy where it might keep someone from messing with my system, if I were ever to have a shop do other work on the car.

Some places are quick to hook up the gauges to see if they can bend you for more $$. They'd balk when they see what I have and haven't done. The first thing they see is R12, but it's clearly not, if they are smart enough to look at the low side, let alone find it.

If they pull it out and contaminate their R12, tough shyte. They shouldn't have been messing with it.

[kuehl]

My suggestion, just based on all the phones call I get where I ask "So, is the car converted to an alternate refrigerant, what kind, how much did you use, what kinda of oil, how much oil, what were your low and high side pressures at idle and the ambient?" At the minimum write it all down and store the notes in your glove box.
Putting the proper conversion sticker on the car along with the data (oil type, amount, refrigerant amount) will remind you too.

If you going to a tech and they are 'quick to hook up gauges' and balk at you? Well, in that case then you are seeking help and when you are seeking help you gotta be up front with them and at least "listen" to what they have to say. You never know, you might learn something listening or at least you'll get an idea with respect to getting a quote from them if you choose to go that route.... and, at least pay them for their time and effort, you never know when you might have to go back and revisit them.

[djnolan]

It looks like I hit upon some very good advice. Since the overwhelming opinion seems to be that 134a works well enough (pressures don't get too high) and is the simplest route I will try it and see how it goes. When I pull the compressor, I was only planning to replace the case o-rings and not the shaft seal but I will look at this aspect as well to make sure I am not overlooking something. The advice on oil seems to be I can add 6-8oz PAG46 (for compressor and dryer) distributed around, to the original oil in the system without flushing. Also clean condensor, oil all seals, low side elbow fitting. Do I have all of this correct?

Many Thanks!

[John_AZ]

Originally Posted by djnolan

Should I start a new thread or just hijack this one?

I have an 85.5 944 with bad compressor o-ring seals and a lot of oil leaked out. I have a seal kit and a new receiver dryer. I was planning for Freeze12 refrigerant. I will replace any disturbed o-rings. How much oil should I add? Seems like all oil in the compressor leaked out. I can only assume the sytem has what is left of the original oil type in it. I would like to make this a permanent repair so going to a little extra trouble flushing and re-oiling etc wouldn't bother me but if I can just put in a few ounces of oil X instead...

thanks!

Here it is Saturday afternoon and I'm staring at a screen. Outside temp is 112F and humidity is about 70 %. Welcome to summer in AZ

OK,
kuehl is a Jersey boy on the golf course having his xxx Becks and matt is in Texas probably with his head stuck in a BMW hood working on the AC in the repair shop.

Your post said you lost a lot of compressor oil. You thought it was the line "O" rings. You were going to see if the front seal leaks. Do you think you may have more leaks and the compressor should be totally resealed?

Do you have a new receiver/dryer? Pelican $11 each or so----must do.
TIP-Pelican sells a HUGE seal kit with the conversion caps and new valves you should also replace--they get old and leak.

http://www.pelicanparts.com/cgi-bin/smart/more_info.cgi?pn=55-9807-901-M325&catalog_description=R%31%33%34a%20Retrofit%20Kit%2 0Contains%3A%20R%31%33%34a%20Charging%20Adapters%2 C%20O%2DRings%20and%20Required%20Label%2C%20%39%32 %38%20%28%31%39%37%38%2D%39%35%29%2C%20Each%20%20% 20

My opinion, If you have already taken the hoses off the compressor to change the "O" rings, you should just remove the compressor and turn it upside down to see if "all the oil did come out". Be careful of the coil wire connection. Do not pull on it--gentle.

Usually nothing will but it will satisfy your curiosity.

It may not be necessary but with the compressor on the bench you could change the 4 manifold "O" rings. Again your choice but why not. If you need "O" rings, AutoZone sells small kits---usually 2 will do--about $6 ea. or find a store that will sell individual "O" rings for R134a usually green or light blue/green.

kuehl asked how I flush a compressor-----matt suggested I pour in some PAG and turn the pully a number of times and then pour every thing out-do not reuse. It will never be perfect but it is a little satisfaction. Never use AC flush.

You might read my earlier post where I suggested to flush/backflush/repeat the condensor to remove the old oil that sits in the bottom tubes and causes poor circulation if not removed. kuehl thought it may not be necessary.

Then measure some PAG and put in slowly about 3 or 4 oz if you can. If you can get more in, add a little more. Keep track of how many ounces you put in.
Keep an ounce or so to pour it in the receiver/dryer---another for the condensor if you flush it.

-Do not open the receiver/dryer rubber caps until you are ready to fill and install.

This should give you about 5 or 6 ounces of oil, maybe more depending on how much you got in the compressor. kuehl thinks 6 to 8 is sufficient.

Remove and replace the receiver/dryer and mount the compressor. Attach all lines and tighten to spec. Yes, put PAG on all new seals to prevent seal "roll".

IMPORTANT Now you have to spin the compressor many, many, many times to get the oil out of the compressor and into the system. A compressor does not move oil----it moves vapor. KEEP SPINNING

Now hook up the belt, attach the coil wire and cross your fingers.

I am sure I forgot something.

GL
John

[marko]

Welp, I started over today. Replaced the drier, ran vacuum for 1hr instead, pressure washed the condenser. With what I believe is the right amount of oil and freon, temp at 90deg, box fan in front of the car, radiator fans at high speed, rpm at 1500, I get 32 low, 260 high, vent temp at 60deg with windows rolled up, recirculate on and fan speed at 2.

If I spray a mist of water on the condenser, the high temporarily drops to about 245. Does it sound like I might need to flush the condenser?