Have the system completely flushed out. Use PAG 46 oil and refill with R12. Some people may say not to use PAG oils but experience shows that using the low viscosity PAG oils reduces failures significantly. The system has to have all the original mineral based oils removed as you never want to mix PAG and mineral oils together. A good solvent flush is required to be sure that all the mineral oil has been removed.

The combination of PAG 46 and R12 will give you the best performance and life possible.

You will need a good flush anyway since your compressor no doubt has shed all sorts of debris through out the system. If you don't flush out the system before replacing the compressor and drier the new compressor won't last long.

__________________
I got too many cars!! Insurance eats me alive. Dave

78 Corvette Stingray - 3k
82 242 Turbo Volvo - Manual - 270k
86 300e 5 speed manual - 210k
87 420sel - 240k
89 560sl - 78k
91 420sel - 205k
91 560sel - 85k
94 GMC Suburban - 90k
97 Harley Davidson Heritage Softail - 25k
00 GMC Silverado 1 ton 30k

Interesting advice. For the last 15 years I've only read that PAG and R-12 are not compatible. Care to share the source of your information?

- JimY

PAG was developed for 134a but it has several advantages over the old mineral based oils that have been used for decades with R12. I know a shop that uses it exclusively because it reduces customer returns to almost nothing. Prior to that he was using mineral oil and had the "usual" number of returns. This guy has been in the business over 30 years. I respect his opinion. I learned about using PAG instead of mineral in a A/C service workshop I took as part of a continuing education course in refrigeration systems. I met a lot of people in the business of automotive A/C repair at the school.

The incompatibility exists between the two lubricants not between the lubricant and the refrigerant. PAG is compatible with either refrigerant. The incompatibility arises when there is a residual amount of mineral oil still in the system and you add PAG. Now you are in for trouble. If you flush clean and use only PAG you are better off than using mineral. Don't put PAG into a system that has not been completely flushed clean of all traces of mineral oil.

My cars use the Denso 10p series and the recommended viscosity is 46. I have done 3 of my 5 cars and the oldest one is running for 6 years now. I live in Houston - it gets a lot of use. No problems or noise. I don't know what compressor you have but here is a table of recommended viscosity for various compressors.

The following is a list of recommended lubricants for compressor applications:

Behr/Bosch rotary compressors - Ester 100
Behr/Bosch piston compressors - PAG 46
Calsonic V5 - PAG 150
Calsonic V6 - PAG 46
Chrysler RV2 - Ester 100
Chrysler C171, A590 & 6C17 - PAG 46
Diesel/Kiki (Zexel) DKS, DKV & DCW - PAG 46
Ford FS6, FX15, FS10, 10P & 10PA - PAG 46
GM A6, R4, DA6, HR6, HT, V5 & V7 - PAG 150
GM V5 retrofit - PAG/FLR-118
Hitachi (all) - PAG 46
Keihin (all) - PAG 46
Matsu****a (all) - Ester 100
Mitsubishi FX80 - PAG 100
Mitsubishi FX105 - PAG 46
Nihon (all) - Ester 100
Nippondenso 6P, 10P, 10PA, 10P08E - PAG 46
Nippondenso SP127, SP134 & 6E171 - PAG 46
Nippondenso TV series - PAG 125
Panasonic (all) - PAG 46
Sanden SD500 & SD700 - PAG 100
Sanden SD710, SDB, TV & TRS - PAG 46
Seik-Seiki (all) - Ester 100
York/Tecumseh - PAG 46

Compatibility statements;

http://www.pag-idemitsu-usa.com/page_200.htm
http://www.pag-idemitsu-usa.com/page_209.htm

A few other sites where information is more difficult to find;

http://www.patentstorm.us/patents/5372737-description.html


Try it - you will like it.

__________________
I got too many cars!! Insurance eats me alive. Dave

78 Corvette Stingray - 3k
82 242 Turbo Volvo - Manual - 270k
86 300e 5 speed manual - 210k
87 420sel - 240k
89 560sl - 78k
91 420sel - 205k
91 560sel - 85k
94 GMC Suburban - 90k
97 Harley Davidson Heritage Softail - 25k
00 GMC Silverado 1 ton 30k

before anything you better see if you have black death.
is so then flushing will not help you.

george

Thanks,

Yes, I'll have to check that...I've been thinking about that potential problem since yesterday when it seized.

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1993 190E 2.3
2001 SLK230
1971 LS5 (454) Corvette Convertible

Is it really possible to remove ALL the mineral oil? Seems like some would surely stay in some nook or cranny somewhere.

__________________
2012 E350
2006 Callaway SC560

There in lies the trick...it's nearly impossible to get All the old oil out.. To do the best possible job one must remove the expansion valve to get a proper flush.

Jonathan

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