The culprit....

It is clear that you have a mix of copper and aluminum there.

Yes, but I just really don't think the leak is at the copper/aluminum joints. The leak seems to be out in the core itself. The evaporator in my other car had leaked in the same way at the same place.

But the truth is, I can't tell EXACTLY where the leak is. I'd love to know, though.

Here are photos of the other evaporator...

Hi brewtoo, I remember that job you did to replace the evap a few years back. You took a whole bunch of photos and replaced the drain hose with clear plastic ones. Nice job. Are you sure the evap did not spring a leak again?

This is a different car this time.

:)

So how is the AMC evaporator that you put in that other car (2007?) holding out? Do you think it will last a while? I have been wanting to do the evap on my 260e but thought about getting a genuine mercedes evap since its so much work.

Well, the ACM I used last time did just fine for about two years, and then the car was totaled when hit from behind.

Do you have a genuine mercedes evap that is leaking now? Why would you want to install another one just like the one that has failed you?

That's what I was about to say. The reason for these evaporators having such a high failure rate is because of the "genuine MB" part. The aftermarket version, by all reports, is far superior.

The LAST thing I would want to do is spend my 15 hours replacing the evap only to put in another bi-metalic version.

I'm about done. Larry, if you can replace an evaporator in 15 hours, you are a better mechanic than I! But, I do not get in a hurry. I even enjoy it, except for the frustrating times...so many little puzzles to put together....

Here at the end I've had trouble with o-ring leaks at the expansion valve and also where the pressure switches attach to to drier. Odd. All-new green o-rings, and the right ones, too. Oh well, better to catch it under vacuum than under pressure!

Another thing I re-learned on this project. Putting things back together is much more work than getting them apart!

I kept close eye on my time when doing a podectomy. I really believe the evap job would be very close to the same job unless you were also doing the pods. My fifteen hours is for replacing the evaporator, not the extra time for evacuation and charging.

Also, when I did the pods, it was with the car on the lift and raised a foot or two for convenience. The podectomy was something slightly less than fifteen hours, so I'm thinking I could do it in fifteen.

My brother in law is a tech at the MB dealership and he calls it a fifteen hour job.

For the average DIYer, I think fifteen hours would probably be an aggressive estimate. Although I am not currently a tech for a living, I have quite a bit more bolt twisting experience and practice than a DIYer.

I decided to heck with replacing this dang evaporator! Way too much trouble to do myself, and way to expensive to have it done!

This was easier. And cheaper. And faster...

GREAT SOLUTION! And it's guaranteed you'll have the only one in town.

Wouldn't it be fun to diagnose the problem with the factory a/c in that car? Odds are very good that it could have been fixed for less or equal to the cost of the generator and window unit.

In the seventies, I was in a ten week Postal Service Maintenance training class where part of the curriculum was refrigeration. We were told that the refrigeration needs of a car was close to that of a small house due to the heat generated by the drivetrain and all the glass giving it such a green house effect. Then a couple of years ago I saw on a truck forum where someone put a small window unit in the bed with a hole cut for access to the cab. He said it cooled like crazy. As I recall though, he used an inverter and didn't use the generator.

What a great picture!

Yes I still have the genuine evap and I suspect its leaking. Last time I changed out the heater blower fan I was able have a peak at the evap and it was all rusted out. So as far as I know its shot. Now the other components such as the compressor etc could be gone too, but I won't know unless I take it in for a leak check. Car is old, 1987 260e

The rust you're seeing is on the outside. It is no indication of whether or not it is leaking. The outside is subject to exposure to lots of condensation. DO NOT ASSUME that a 124 evaporator is leaking because it is a 124 evaporator.

If it ain't broke, don't fix it.

OK, the fun is over...