compressor o-rings
 

I'm replacing the Nippondenso Compressor (10p17c) on my '87 560sl and realized that I need new o-rings for the suction and discharge fittings. Wanted to finish the job asap, and just went out and got new o-rings that are dimensionally the same as the old ones. Will this do or are the Mercedes o-rings special? If they are, where can I puchase them?

Thanks!!

if they are demensionally the same, made of appropriate material, have the same compliance and heat tolerance, then they will probably work.

if you wish the appropriate part for sure, I might suggest the MB dealer. You will be surprised on the cost of those o-rings but it will be hard to be sure otherwise.

Depends on refrigerant...
 

Hi there,
The answer really depends on what refrigerant the car uses. If it is using R12, the neoprene O-rings will be ok, as long as they are an appropriate size. If you have R-134a, they will leak. The molecule size of R-134 is much smaller, and with new O-rings there will be no old oil to plug up the microscopic holes in the O-ring's rubber, allowing the R-134 to pass through. R-134 requires barrier hoses and special O-rings to keep leakage down to an acceptable level, when using new parts. Old hoses seem to work ok without excessive leakage because they are saturated with a surface coating of oil. Most R-134 conversions seem to require yearly "topping off", if they last a year. This is because the molecules of R-134A can and do pass through the rubber of the O-ring seals and hoses.
Richard Wooldridge
'82 300D/4.3L V6
Etc...