cleaning evaporator in place - W123? - PeachParts Mercedes-Benz Forum

::matthew · #1 07-03-2009, 08:45 PM

I know that JimmyL had interest in this and I'm wondering if it can be done. Although I don't know the condition of the evaporator, I imagine it's safe to say that it's filthy from 24 years of use.

I'm not prepared to perform a dashectomy, so if that is required, I'll wait.

79Mercy · #2 07-03-2009, 08:50 PM

they sell stuff that you spray in the vents, but I doubt it works very well. Otherwise it must be removed and cleaned.

leathermang · #3 07-03-2009, 09:09 PM

I am interested also...but also will not be doing a dashectomy...
I am thinking there may be one or more places which could be drilled to give access to a spray nozzle which could reach over the coils to spray some effective solution. Then patch the holes with RTV or fiberglass and go about fixing the rest of the system to match your nice clean Evaporator.... that is my dream.

wgilmore · #4 07-03-2009, 11:01 PM

I've tried 2 products - Nu-Calgon and Klima Cleaner to clean evap coils in place.
I found the Nu-Calgon to be a pretty good cleaner.
The Klima Cleaner just wasn't as aggressive, left an unpleasant odor and did not clean very well.
Used Nu-Calgon in the 528 , the SDL, and Volvo.
Used the Klima cleaner in a friends pimp-mobile AKA Cadillac something (due to wife's sensitivity to odor - what a mistake), did not remove much gunk.

In the 126, I did the fan removal approach and got quite a bit of yellow - brown junk out with the Nu-Calgon evap cleaner - the self wash type.
I did use a brush and water to help and did not rely on the evap condensate.
Sprayed cleaner and rinse water every where I could including both drains.

leathermang · #5 07-04-2009, 02:42 AM

Did you use a spray nozzle on a wand or something which allowed you to get up near the fins...or did you spray from the fan air inlet only ?
I am hoping a 123 is less work than any other model... it is simpler on so many items....

wgilmore · #6 07-04-2009, 03:16 AM

Quote:

Originally Posted by leathermang

Did you use a spray nozzle on a wand or something which allowed you to get up near the fins...or did you spray from the fan air inlet only ?
I am hoping a 123 is less work than any other model... it is simpler on so many items....

When I applied the foam through the drain nipples, I used the tube that came with the Klima cleaner. It is maybe 2 ft. in length and has a brass nozzle on the end of the tube with about 4 holes in it to disperse the foam.
I also did the "remove fan assembly" and could get my hand to the back side of the evap. I sprayed foam from there also as well as rinse water. I used a small brush on the back side of the evaporator. There seemed to be a lot of carbon from the fan brushes coating the evap core. I noticed that the previous owner had replaced the blower just before my purchase of the car. Overall not too much work.