Uprated W126 A/C condenser

When I purchased my 560SEC, the A/C was not working.   It hadn’t even been converted to R134A.   I suspect it had never worked while in Australia.   The car came out of Queensland, and I’m not sure I would want to drive a car without a car up there.   The long time owner was in the Army, I guess tougher than me!    When I purchased the car, I first concentrated on the important stuff like the timing chain.   After that was sorted out, I had the A/C converted and charged up.   It’s no longer possible to buy R12 in Australia unfortunately.

While I had to do a few things to the climate control system, the A/C worked pretty well after being charged up.   The main issue was a leak from the compressor.   For a while, I was able to get away with charging it up annually, but recently it was degrading pretty quickly only a couple of months after a charge.    It was obvious that the leak was coming from there by using a blacklight.

Since I was already having the compressor changed out, I also thought this was an opportunity to try and upgrade I had been considering for a while.   Klima Design Works offer an uprated W126 A/C condenser that is designed for R134A.   R134A is not as efficient as R12, and this uprated W126 A/C condenser is billed as 30% more efficient than the stock unit.    That help restore the A/C performance lost through R134A.

I did some research on the various US forums and found good feedback from W126 owners in climates like Texas and Florida.   Basically the consensus seemed to be to either use R12, or this upgrade.   The upgraded W126 A/C condenser comes with the requisite brackets and hoses to interface with the W126 A/C system.   They offer two types depending on year and model.

Obviously, since I was having the compressor changed as well, I supplied a new receiver drier and TX valve to be installed alongside the compressor.   Like with my 300SE, I went with a brand new Denso compressor.   I’ve not had a lot of luck with rebuilt A/C compressors in the past, and given the high labour cost to have it installed, its much better to go with new.

While the car was in the shop, the front brakes were attended to.   On a recent brake pad change, I noticed that one piston on the front drivers side was not moving at all.   I ordered the rebuild kits, plus pads and a new set of front rotors.   My rotors were pretty crusty and within 2mm of the wear limit.   A good time to change them.   The rebuild kits were advertised as Bendix, but my mechanic later told me they were actually ATE units.   This was really annoying as I paid quite a bit more for these kits.

In doing the install, my mechanic told me that the fit of the uprated W126 A/C condenser was really tight.   This probably added a bit to the cost, but in my mind is a good thing as its using all available space for cooling performance.     There was also a little bit of interference between the secondary air snorkel on the 560.

The other issue he ran into during the install was the missing aux fan guard caused a rag to get sucked into the fan and damage it.   This was a problem with the Meyle auxiliary fan I installed a couple of years ago.   Since then, they moved to an improved design that does fit the fan guard.  I have that one on my 560SEL.   I’ve ordered one of these fans to fit to the car.

So far the weather has not been hot enough to really test out this upgrade.   We’ve had one day where it was about 25c and fairly humid and the A/C worked very well.   Better than before.   However, It was previously able to handle days like that.   The real test is when the temperature gets up into the high 30s and humid.

I’ll use this summer to see how I go.  If I’m really happy, I’ll also fit this uprated W126 A/C condenser to my 560SEL.   On really hot days the A/C performance is sub par.  A new TX valve would improve things I am sure.  However if this upgrade works really well, I may do it too.