Idoktr

I need a recharge for the 87 944S. I really do not want to sink more $$ now into a retrofit. Can I just have the old system recharged, and how much should it cost??

badcoupe

You might as well retro it as the R-12 is extremely exspensive and hard to get nowadays. You need to flush all of the old oil out os the system by taking the lines and using a flush just for A/C systems. then put it together and vacuum it down and then charge with the required amount of 134. Oyy yeah don't forget to add new oil that is 134 compatible. you could just add new oil which doesn't mix with old very well and vacuum it down and then charge with the new and have a temporoary half a$$ fix. I'm guessing that in your area they charge quite a bit to retrofit. Here at my shop It usually starts as 85 and goes up depending on if you ned new lines, how much refrigerant etc.

83na944

Idoktr,

R12 cost about $2 an ounce last year. The system holds about 30 ounces. So the maximum for R12 is about $120, give or take a few bucks for inflation and labor.

The real hitch is if the shop goes by the law, they have to assure that the system does not leak before they charge it with R12. So if any component leaks, they need to repair it before they can charge it. Since this means more labor for the repairs, they usually take this seriously (cynical view).

If you take to a shop, they'll leak test it and tell you if there are any repairs needed for about $25. If it is leak free, they can top it up for you. If there are leaks, at least you'll know what needs to be repaired.

BTW, I saw a message last night that said that the US had signed the Kyoto accord and that R134a will be under the same restrictions as R12 in 8 years. I don't know if this is true.

83na944

Follow-up to my post. I searched the news and found no mention of the US signing the Kyoto accord.

951Tom

83na944, When I took my 609 certification, I think they mentioned that you'd still be covered if R134 ever requires a license to buy. Buy it now while it's cheap!

Kevin Baker

Local laws vary, check your regulations. In some areas it IS NOT illeagal to refill a leaking a/c system. We normally charge $140-160 for evac and recharge with r12.

83na944

Kevin, I thought this was a Federal law. Is it state or local?

And $160 seems like a fair price considering the time and equipment involved.

Tom, I think I saw that the certification would also cover R134.

Kevin Baker

According to clean air act "...EPA recommends that all leaks be repaired prior to recharging the MVAC system." From IMACA study guide to sec 609 of the Clean Air Act.

Luis de Prat

Idoktr, how long was it since your A/C was working? If it's not completely empty, one thing you can do is have a pro A/C shop vacuum whatever is left in it and then recharge it yourself with a R134a conversion kit.

I did this to my 83 a few months ago and it's been working really well. The Interdynamics kit cost around $40 at a local Western Auto Parts store and all I had to do was raise the front end of the car and pop the hose on the Sanden compressor intake.

The cans of refrigerant come ready mixed with lubricant, so you don't have to add any oil. Worked like a charm for me, and I need working A/C year round here in the Caribbean.

YMMV

Don 944 LA

Jumping in here with a question....:

So, if you have no idea what condition your inoperable AC system is..
I should, Have it checked out for leaks and R12 vacumed ??
Then those cheap auto store kits with the fitting adapters will do the trick ??

If so, thats what I'll do. That way, if my compressor don't come on afterwards, I'm not out a bunch of money to replace R12 twice.

I am also aware of the majority opinion that R134 is not as cold as R12.. but what ya gonna do ??

Kevin Baker

Just make sure that the system is completly empty. The oils from r12 systems and r134 are not compatible. Please also install both the r134 fittings and the lable telling when it was converted and what to. Almost had a $5,000 134 recycle machine ruined by a DIY'er who didn't fill us in completly.

Kevin Baker

Don, yes have the system evacuated. Then if you would like, you can add the 134. My system was completly empty when I bought the car, I gambled that the 134 would work, and it does. My thinking was along the same line as yours (what the worst? It wouldn't work at all). r134 has VERY similar temp to pressure values when compared to r12. The performance of r134 only falls of at the extreme upper end, much above what you would be seeing in our a/c systems.

Kevin Baker

Also, Don check to see if there is a High Pressure Cut off switch on your system. r134 can run at a higher pressure than r12. If you overcharge the system you CAN break stuff, like exploding lines, fittings, etc..

Luis de Prat

FWIW, my 83 on R12 cooled nowhere near as well as it does on R134a. I'm guessing the new Sanden compressor is more effective than the old stock Nippondenso was, but still, it gets pretty hot here in the tropics and I'm quite satisfied with the R134a.

83na944

Don,

Do you think the compressor is not operating because of low R12? If so, you can jump across the terminals of the low pressure switch connector and then switch the ac on. If the compressor clutch is ok and the compressor is not locked up, the clutch should energize and turn the compressor. Just don't run it longer than necessary because if its low on oil it could damage the compressor.

And take Kevin's advice. If you do the conversion, have the R12 recovered and the system evacuated.