Ducman82

so i am about in install an new Denso compressor, and it calls for ND-OIL 6. what PAG oil is that, 100 or 150? i cant seem to find that info out.

pjg

The R-12 system uses mineral oil, R-134a uses Pag-46, if you are retrofitting to r134a than a new dryer and o-rings will be needed.

928 SERIES
95-93 All Eng. R-134a 30.00 PAG-46 9.00 409503 409888
91-89 All Eng. R-12 33.50 Mineral 9.00 209500 --

Ducman82

well i got a new compressor and dryer from my local porsche shop. while i was swapping over the fittings on the compressor, i noticed the new compressor says r12, the old one does not. but everything is the same. now the tech that drained the system for me said it was r134 due to the fittings. so im guessing that at one point it was changed over to R134a. so i need PAG46, not 100 then, would be my guess.

pjg

ND-Oil 6 and 7 are mineral oil for R12 only, confirm that you have an R-134a system and use the Pag-46 oil.

http://www.toyotapart.com/AC_COMPRES...T-AC93-005.pdf

More reading here on compressor oils.

http://www.motor.com/article.asp?article_ID=1015

Ducman82

well, its got teh R134 nipple adapters on it so it has been converted. so pag 46 oil. looking at the directions for the compressor, i should compare the oil in the old one with the new one. new one does not have the drain like the old one... so, one bottle of oil should do it for the whole system would be my guess.

if i was in Idaho still, not new mexico, i would just leave it all off.

jake

pjg

You need to take into account the oil that is left in the evaporator, condenser, and hoses. As long as you have no leaks in the system if you measure the amount of oil you get out of the old compressor and add that amount to the new one you should be OK.

From the WSM 87-103
Dlstributlon of oil In refrigerant circuit

Compressor 40%
Evaporator 35%
Condenser 15%
Fluid tank / lines 10 %
These values are approximations.
If a replacement component is fitted, top up
the oil by an amount equal to the quantity left
in the component removed.
The correct amount of oil can be poured
into the new component.
If a replacement compressor is fitted,
60% of oil must be drained from the new
compressor which contains the quantity for
the entire system.

dprantl

I would not use PAG oil in a converted system. Ester oil is what is recommended. I would drain all the oil out of the compressor, flush the rest of the system, then add the correct amount of ester oil.

Dan
'91 928GT S/C 475hp/460lb.ft