Suction port seal on newly installed new compressor leaking HELP.
 

Hope you dont mind me bugging you but another BIG problem:

Pushed some air from the other end of suction port ( the one that fits on exp valve- exp valve is removed for replacement) on the newly installed R4 compressor to check if there is a leak and found that the yellow seal ring on the suction manifold on AC compressor is leaking air.The ring looks like it had seated properly in the compressor port but still leaks. The manifold bolt is fully thight. The discharge port seems to be holding good. What do I do?? Could it be the difference in the thickness of the seal ring?? Should I start the compressor installation process all over again??

mvk

Yep - these are a pia to sort out because there are so many combinations. The correct o-ring seals should have come with the compressor, or it did in my situation when I changed it out on the 300D. Do you still have the ones that came off? Anyway, you do not have to remove the compressor but you do need to find the correct o-ring. If I remember correctly they are different thicknesses/widths. Try to find an automotive a/c supply house and take what you have to them and tell them/show them which one is not sealing. You may have to purchase two or three different sizes but the correct one is out there.

Thanks for a quick reply Jim. Yes they came with the new compressor. Also these are not o-rings, since the compressor is with the stepped ports, thsy are like metal rings with rubber center. I think they are called sealing rings( I am not sure).
I will try differnet ones lets see what happens.

Any other suggestions welcomed.

MVK

Check out these guys... and consider bookmarking their address...

http://www.caawparts.com/

use the toll free line and call to talk to TREY .

He is Trey Carlisle...of Carlisle Auto Air in San Antonio....

I know that this response is delayed but the archieves are great. I recently purchased a new compressor also. The compressor came with the same set of metal sealing style rings. Upon close inspection, these rings when seated in the respective seats on the rear of the compressor did not look like they would seat properly to the manifold hose (one side was higher than the other). The manifold hose was removed, and when I tried to match the manifold hose to the sealing rings / compressor on the bench, found that one side would not seat properly to create a good seal . This sounds like the same kind of problem. Anyway, was just wondering what your results were so that maybe I can avoid re-inventing the wheel.

Hi Bob:
I could not get the manifold off. It was too tight and I did not want to mess it up. I tried all possible combination of the seal rings to no success. Finally got tired and put the old one back until I decide what to do.

Also wife and kids are complaining that I spend too much time with MB and not enough with them. Also back pain creeps up once in a while so I am seriously thinking of selling the car.

Still trying to convince wife and kids. But finally it all boils down to family time and family values.

I am also planning to return the compressor even if I have to pay restocking fee of upto 25 bucks.

This AC project was a real turn off. I think its almost impossible to get a good seal with the stepped port compressor when the manifold was not designed for it. Let me know how it goes with you.

MVK

EUREKA!!!!
Go to Fastlane, Year, Model. Etc, Climate Control, O-Rings. The middle o-ring there is the metal type for R4 Non-Stepped Ports. If you use the large brass o-ring that came with the compressor kit for the large port and this o-ring from Fastlane for the smaller port, it looks like it will be a great seal. These o-rings are the exact same height. They are a little too tall but the manifold line bolt only takes about 30nm. I don't think that will create any distortion on the manifold line. There will be a small space between the compressor and manilfold pipe which the instruction sheet says no problem. I am going to proceed with the installation this weekend and evacuate and charge on Monday of next week. I'll keep you posted. Have to agree about this being real PITA project. Make wife has been sending up smoke signals the past few weeks as little progress has been made. Maybe after the A/C starts working she'll COOL off a little bit!

Hi Bob:
I am not sure if they would work. If they do let me know. I will try them.

MVK

Sorry to resurrect a thread from two years ago, but since I couldn't find definitive answers when I was searching, I wanted to post my results.

I have recently conquered this problem. I replaced a bad compressor with a new R-4 that had stepped ports. My old compressor had even ports with internal o-rings, and you simply bolted the hose up to it. Not so here. My compressor came with a thick green seal and a couple of thinner red seals. The instructions laid out a number of combination, none of which matched the set up in the Mercedes. I ended up looking at the Worldpac catalog for the "hose manifold seal kit"; you can see it in Fastlane here.

I got the brass/yellow seal seen in the kit from NAPA, its simply referred to as a "thick yellow seal" for the GM R-4. They had to order it, cost around 4 bucks. It is wide enough that it covers the deeper port, while the green one mates up on the other side. If you are under the car looking at the compressor, and your feet are sticking out the front end of the car, the green seal (with the short pilot) will be on the left side, and the yellow/brass seal will be on the right. Once this was taken care of, everything snugged right up.

Don't be sorry! You 1) searched first, 2) kept it on topic 3)posted relevant info and RESULTS. That's a real benefit to this forum. Compare that to all the "Hey Guys, look what I did to pimp my ride today!" posts. Thank you.

Or "What color shirt were you wearing when you saw your first MB?" Or "How old were you when you first learned to spell 'Mercedes?'"

Amen, Pete.