O.K. ~ 1984 W-123 Diesel with about 400,000 miles on it , the AC volume from the dash vents has been falling a lot over the years , I replaced the blower motor yesterday and took a look inside the plenum using a nifty Harbor Freight remote camera thing , it works pretty well and shows the evaporator is dead black instead of the aluminum color the evaporator is in my same year TD that blows gales of air , leading me to believe the evaporator is covered in the same Diesel smoot the rest of the car's interior is coated with .

I sprayed some purple household cleaning stuff in there , allowed to soak 15 minutes then sprayed in with the garden hose , some crud came out the AC drain underneath the car but I doubt it's actually much cleaner as little air flow is evident .

Here's to - day's question : what chemicals and methods should I try ? .

I am NOT going to do more than removed the blower motor as that opens a 3" or so clear path to get fluids in , if sadly not my hand .

Ideas/ suggestions / what you did please ? .

TIA ,

__________________
-Nate
1982 240D 408,XXX miles
Ignorance is the mother of suspicion and fear is the father

I did then what I knew how to do ~ now that I know better I do better

searching found this.

Evaporator cleaning, scope vid.

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 560SL convertible
1987 190D 2.5-5SPEED!!!

1987 300TD
2005 Dodge Sprinter 2500 158"WB
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

THANK YOU ! .

I'm off to give that a look .

__________________
-Nate
1982 240D 408,XXX miles
Ignorance is the mother of suspicion and fear is the father

I did then what I knew how to do ~ now that I know better I do better

Speaking with W126 knowledge, only. It was not hard to clean my evaporator but it did take some time and tedious work. It also helps if you have small hands.

I tried the coil cleaner method but I was not impressed with the results. It did not remove much, if any of the debris on the evap fins. I then started a manual approach with a brass brush and my arm inside the AC box. I got good results on the surface but I could tell that more debris was inside the fins. At that point, I decided to use a garden sprayer to soak the evap core in drain cleaner. I would dilute it 50/50 next time because it started working too well. There was steam/smoke pouring from the vents as the drain cleaner digested the years of organic matter lodged in the evap core. Since it started getting hot, I decided to apply a generous amount of water to dilute and wash away the drain cleaner. In the end, the evap core was shiny and clean. The AC performance increased about 15% in cooling efficiency.

I also vacuumed the evap core box out using a heater hose attached to my vacuum cleaner. There was a lot of debris in there.

The lesson is that if you use drain cleaner, dilute it and don't let it sit for too long but it works a lot better than evap cleaner.

__________________
1991 F250 super-cab 7.3 IDI. (rebuilt by me) Banks Sidewinder turbo, hydroboost brakes, new IP and injectors.
2003 S430 - 107K
1983 300SD - Tanoshii - mostly restored ~400K+.
1983 300SD - Good interior. Engine finally tamed ~250K.
Monark Nozzle Install Video - http://tinyurl.com/ptd2tge

here are a few thread, some on cleaning the Evaporator and some
showing some nasty looking Evap`s., and why you can`t just flush them
with some spray miracle wash.
You might get some out, all depends how through you want to be.


Clean those evaporators!


Blower motor repair / evaporator cleaning 84 300D W123

evaporator out of the 300TD

Manual Climate control swap



Charlie

__________________
there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

Maybe this will help you take on the real job. The ACC airbox is similar to the Manual airbox.

How To Disassemble A W123 Manual Airbox Photos by daw_two | Photobucket

Reassembly is the same link; start at the last pic and work your way toward the front.

__________________
daw_two
Germantown, TN

Links:
Sold last car --- 05/2012 1984 300D Light Ivory, Red interior
No longer selling Cluster Needles Paint
No longer selling New Old Stock (NOS) parts

Past:
3/2008 1986 300SDL "Coda"
04/2010 1965 190D(c) "Ben"
& many more

make sure you get the cleaner that contains the long flexible hose for routing it into the case. i used kool-it brand and thought it worked great. some people swear by einszett. both have the hoses.

make sure the drain tube that goes from the evap case to outside the body isn't destroyed! its just a flimsy foam tube that is often disintegrated. when you start spraying cleaner and water in there it will flood the floor if that tube is busted or missing! you dont want that gunk all over your carpets.

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1981 NA 300D 310k miles

THANK YOU ALL ! .

I appreciate the various interconnected links .

My hands I think are too big to fit inside .

I have zero plans to take the dashboard apart , I'm an old Man now and crippled to boot .

The Evaporator box drain tube is easily visible from the passenger side foot well and is fine ~ I ran my garden hose in and it didn't drip one drop on the inside of the car (whew) .

I guess i'll have to go look for the stuff with the hose to get it in there ~ I tried spraying some purple cleaning stuff in there but have no idea how much of the Evaporator it actually touched , my Cheap Harbor Freight inspection camera works fine but looks in at an angle , not directly down across the fins .

I _can_ see the Evaporator is black unlike the one in my TD , it's the same year car but is still aluminum colored .

i have the front of the car apart for new Condenser and SANDEN compressor so it'll be a while before I get back to this cleaning .

I installed the new URO brand blower motor , it works fine but is somewhat noisier than the old original one .

I need to figure out how to open the center vent flap , I did it a few years ago but it's closed again and I'm betting the vacuum element is bad from old age now .

Again : THANX FOR ALL THE HELP & REPLIES !

Remember : I will NOT be taking the dashboard apart .

That's Young man's work , I am not young & flexible any more .

__________________
-Nate
1982 240D 408,XXX miles
Ignorance is the mother of suspicion and fear is the father

I did then what I knew how to do ~ now that I know better I do better

Break off a small chunk of mirror and RTV it at a 45 deg angle to the camera. Voila!

__________________
85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

Thanx (maybe) .

That's an idea and I do have an extendable 1" mirror but I have a broken spine and neck , three holes in my (admittedly empty) skull so the contortions necessary to make that work don't sound possible......

I'm more pondering how to reach in there with a soft bristle brush for my next attempt at cleaning .

This Forum is always so helpful in answers and in helping me to think out side the box in general .

BTW : is there a ' 240D's are too slow ' thread ? I'm driving SWMBO's clean old Slush Box equipped '82 until my Coupe is road ready again and was thinking about that aspect of it .

TIA ,

__________________
-Nate
1982 240D 408,XXX miles
Ignorance is the mother of suspicion and fear is the father

I did then what I knew how to do ~ now that I know better I do better