A/C o-rings ?

[Peter M.]

I have two different type o-rings for my R12 AC system. The original o-rings are black and thicker than the new thin green o-rings. Are the new green rings for R134a and the thicker rings for OEM R12 or does it matter?

[Jake D.]

Re: A/C o-rings ?

Green = R134A
Black =R12

[Peter M.]

Re: A/C o-rings ?

Green = R134A
Black =R12

[Larry M.]

Re: A/C o-rings ?

Peter:

Agree with Jake regarding the colors, but I would also be concerned if the inside and outside diameters were different than originals.

O-rings are designed to work correctly within certain tolerances, so a thinner o-ring may seal initially and then fail, or may not seal at all.

What year car and refrigerant are you using? And where did you purchase the o-rings? Where do the o-rings go?

I have Delco and GM part numbers for most of the o-rings, if you want to pursue. Also kit numbers for various year GM cars that can be obtained from large on-line auto AC supply companies. Also, the green colored o-rings (HNBR) should work for both R12 and R134a.


Larry

[Dick W.]

Re: A/C o-rings ?

The green, if properly sized, will replace the black. I have not used a black 'o' ring in years and have not had any problems.

[Peter M.]

Re: A/C o-rings ?

Peter:

Agree with Jake regarding the colors, but I would also be concerned if the inside and outside diameters were different than originals.

O-rings are designed to work correctly within certain tolerances, so a thinner o-ring may seal initially and then fail, or may not seal at all.

What year car and refrigerant are you using? And where did you purchase the o-rings? Where do the o-rings go?

I have Delco and GM part numbers for most of the o-rings, if you want to pursue. Also kit numbers for various year GM cars that can be obtained from large on-line auto AC supply companies. Also, the green colored o-rings (HNBR) should work for both R12 and R134a.


Larry

Larry:

All for 1986 roadster which will be running OEM R12. These o-rings are for the A/C lines from evaporator to accumulator and from the A/C compressor to the condenser. The smaller rings are for the oriface tube line and the low side return from the condenser to the evaporator. The new rings came with the replacement refrigerant lines and, I am sure, are intended for use with R134a.

[Larry M.]

Re: A/C o-rings ?

As both Dick and I have already said, the green colored (HNBR) o-rings are compatible with both R12 and R134a.

If they came with the replacement metal refrigerant lines, they should be okay. Just use a little bit of R12 mineral oil when installing to prevent cutting/scuffing of the o-ring.

For what it's worth, the green HNBR o-rings have better chemical resistance and higher temperature resistance than the old black ones.

Larry