W126 A/C System Rebuilt - Condenser Source - PeachParts Mercedes-Benz Forum

floydla1 · #1 01-16-2022, 09:13 AM

Hello Gentlemen,

Can someone recommend a good brand A/C condenser and where I can buy? All my standard sources are reporting "out of stock". O'Reilly says they have a "Murray" condenser for $300, but I know nothing about this brand.

Background: Time to give the 300SD some TLC. The replacement A/C compressor blew (R134A system) about a year ago. I have assembled the replacement parts -- all but the condenser (original). I reviewed a lot of the existing threads and am now persuaded that I should also replace the condenser. Parallel flow design appears to be the way to go.

I did this job about 8 years ago (including expansion valve) -- its a big job, and only want to do it once.

A special thank you in advance for the posts on system flushes.

automch · #2 01-18-2022, 08:19 AM

Be sure to flush the lines and allow them to dry. The main reason R4 compressors fail is lack of lubrication. I learned this trick working in a Ford Dealership in Ft Lauderdale in 1995. Ford was having a lot of compressor failures after changing to the required R134a and sent out this bulletin that said, put 4 ounces of R12 Oil (Mineral Oil) directly into the compressor before installing it and rotate the compressor to distribute it among the internal parts. Then install, evacuate and add required system PAG oil and charge the system. I retired last year after 50 years professional work in the automotive business. I have found this works very well. My 83 300SD has had 3 compressors since new. The one on it now is 11 years old and is quiet and works fine. I have posted this before about the mineral oil and drew a lot of criticism from some who did not like the idea but it works. It seems the R134a will not carry the mineral through the system and it will stay in the R4 compressor. The R134a will still lubricate the rest of the system by carrying the PAG oil as it circulates. As for your original question I do not have a current source but Murry is a valid aftermarket vendor and make quality components. Hope this helps.

JHZR2 · #3 01-18-2022, 09:42 PM

Quote:

Originally Posted by automch

Be sure to flush the lines and allow them to dry. The main reason R4 compressors fail is lack of lubrication. I learned this trick working in a Ford Dealership in Ft Lauderdale in 1995. Ford was having a lot of compressor failures after changing to the required R134a and sent out this bulletin that said, put 4 ounces of R12 Oil (Mineral Oil) directly into the compressor before installing it and rotate the compressor to distribute it among the internal parts. Then install, evacuate and add required system PAG oil and charge the system. I retired last year after 50 years professional work in the automotive business. I have found this works very well. My 83 300SD has had 3 compressors since new. The one on it now is 11 years old and is quiet and works fine. I have posted this before about the mineral oil and drew a lot of criticism from some who did not like the idea but it works. It seems the R134a will not carry the mineral through the system and it will stay in the R4 compressor. The R134a will still lubricate the rest of the system by carrying the PAG oil as it circulates. As for your original question I do not have a current source but Murry is a valid aftermarket vendor and make quality components. Hope this helps.

That’s a good trick, I’ll have to remember that if I adopt a vehicle to r134.

engatwork · #4 01-19-2022, 09:07 AM

Regarding condenser measure opening for it and buy a parallel flow one that will fit opening. You will have to get hoses rebuilt/modified. Make sure you pay attention to location for hose connections where you can attach hoses to it after install. Shop around for condenser on automotive parts sites. Lots of choices and cheap too.

H-townbenzoboy · #5 01-21-2022, 02:33 PM

I had the same issue and ended up getting a parallel flow from Klima Kit.

BillGrissom · #6 01-21-2022, 05:44 PM

If changing the hoses too, might be an opportune time to install a better aluminum parallel flow condenser. There are many on ebay for ~$50 and give dimensions. You will have to fab some straps, but usually easy. I did that in my 1960's Mopar cars. Best to get one with common O-ring fittings (usually #8 in, #6 out liquid). You can get inline reducers if your compressor outlet hose differs (might be #10 for my R-4, I forget). No need for a ferrule crimper, though that gives a factory look. Oeticker stepless ear-clamps work fine (can use 2 each end) and look almost factory. Some sizes of PEX tube ferrule crimps might work.

floydla1 · #7 01-29-2022, 11:43 AM

Hello All,

First, I apologize for the delayed response. I am presently occupied with replacing the front seal and spacer on the crankshaft (btw, anybody got a trick for pulling the spacer, mine is being onery).

Second, thanks much for the responses:
For the mineral oil, the new compressor says it is precharged with 3 oz of oil, but no idea what type. I have FJC Estercool, which is a mix of mineral, PAG, and esters -- says it is compatible with R12 and R134A. So, I will add 9 oz of this directly to the compressor. AUTOMCH -- do you approve, or should it be exclusively mineral oil?
Hoses: Since there was possible compressor frag, I am replacing all the hoses up to the firewall.
Parallel flow. I am looking at the Klima webpage as I write this. They are showing them on backorder, I'll call them Monday, and will look at what is available on e-bay in the meantime.
Again, great suggestions all!