I recently replaced the evaporator and 6 vacuum pods on my 1993 400E. Here are reflections on the work I did on my car that may apply to yours as well.

See http://photos.wanadoo.co.uk/album/1259925 for pictures of a W124 dash removal.

Very carefully read all posts on the thread, “Help W124 Evaporator” by Jcyuhn, he is very knowledgeable.

A T-27 Torx bit with a minimum 2 inch long shank was needed for removing the steering wheel air bag

Three new o-rings for lines going into heater core were needed.

Two new o-rings for lines into expansion valve were needed.

Four new o-rings were needed for the new receiver/dryer.

I needed two new foam condensate drain lines from Mercedes or, as a much cheaper alternative, I used about 10 inches of 3/4 inch ID vinyl hose.

PAG oil was specified for lubricating heater and air conditioner o-rings. I bought an 8.5 ounce can at Advance Autoparts for about $6.50. Approximately four ounces of the PAG46 oil was also added to the system prior to evacuation and recharging.

I did not take enough photographs of the disassembly; sometimes had to reply on faulty memory.

I did not always bag and label all fasteners and ended up with leftovers.

I removed the center and left hand air vents before trying to remove the instrument cluster. With the vents removed, the cluster was gripped with fingers at each side and wiggled out without the use of the cluster removal tools.

There was a difficult to open, postage stamp size door on the center vent that retains the bulb and its holder.

The rocker switch assembly was removed by gently pushing it laterally to the left, or right, and then gently pulling it straight back.

I needed to more carefully record location of vacuum lines from the plastic manifold, on the right side of heater box, to the pods. I got them mixed up.

I found that clips holding together the heater box, tended to jump like frogs during removal.

I loosened the clamp holding the low pressure refrigerant line located on the forward firewall to get a little more wiggle room when trying to fit the line into the hole in the expansion valve.

I'm sure there are folks here who will find the list helpful. I would not offer criticism to your list if it were not a safety issue so please forgive me.

You say that you used PAG oil to lubricate o-rings. I would NEVER advise this. PAG oil is a seriously dangerous oil, VERY carcinogenic(sp?) A better choice for this purpose is something called Nylog that can be bought at any auto a/c supplier. It does a better job with no health risk and especially designed for the purpose.

The other thing is that you obviously chose to remove the steering wheel as did I. It was not a big deal, but I would URGE those who choose to do so to read the instructions carefully on disarming the air bag. Also make sure you store it with the air bag up. This way if it were to deploy, one would be hit by the soft airbag rather than the heavy base that would traveling at tremendous speed.

Glad you got the job done, and thanks again for your list.

Larry, I was alarmed by your comments about PAG oil because not only had I gotten the stuff all over my fingers, I spilled a bit on the bench and then put my forearm down in it! I found several Material Safety Data Sheets for the stuff on the web but none mentioned toxicity or special handling. Please advise. Thanks, Frank

http://www.virginiakmp.com/msds/LPG68D.pdf

doesn't indicate carcinogenic effects, however other msds sheets indicate pro-arrhythmic effects of a/c charging kits.

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89 300te 222,222
92 300e 190,000

Maybe I'm wrong and I can't remember where I got that idea. But I was under the impression that it is nasty stuff.

Good luck,

I think PEG is a suspected carcinogen, but that's something in soaps and cosmetics...

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89 300te 222,222
92 300e 190,000

I continue to gather information for my anticapated fall/winter removal of dash to replace vacuum elements.

I don't quite see why you would have to take the steering wheel/airbag off. Am I missing something here?

[QUOTE=flanso]I recently replaced the evaporator and 6 vacuum pods on my 1993 400E. Here are reflections on the work I did on my car that may apply to yours as well.


A T-27 Torx bit with a minimum 2 inch long shank was needed for removing the steering wheel air bag


.

I did not take enough photographs of the disassembly; sometimes had to reply on faulty memory.

I did not always bag and label all fasteners and ended up with leftovers.

I removed the center and left hand air vents before trying to remove the instrument cluster. With the vents removed, the cluster was gripped with fingers at each side and wiggled out without the use of the cluster removal tools.

There was a difficult to open, postage stamp size door on the center vent that retains the bulb and its holder.

The rocker switch assembly was removed by gently pushing it laterally to the left, or right, and then gently pulling it straight back.

I needed to more carefully record location of vacuum lines from the plastic manifold, on the right side of heater box, to the pods. I got them mixed up.

I found that clips holding together the heater box, tended to jump like frogs during removal.

I

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1989 300ce 129k
( facelifted front,updated tail lights, lowered suspension,bilstein sports, lorinser front spoiler, MOMO steering wheel, remus exhaust,stainless steel brake lines). (Gone)

1997 s320 154k (what a ride). Sold with 179k miles. Replaced with Hyundai Equus

1994 e320 Cabriolet 108k



1972 280se 4.5 153k Owned for 12 yrs, sorry I sold it


[/SIGPIC]

The MB shop manual advises removal of the steering wheel/airbag before removing the dash. I left it in place when performing the evapectomy. Just run the telescoping wheel all the way out - there's enough room to remove the cluster and get the dash out.

I've not read that PAG oil is carcinogenice. It's known to be a skin irritant, and should be washed off at the earliest opportunity. My understanding is that PAG is quite similar to brake fluid. I always pop for a synthetic refrigeration oil that is not hygroscopic - less worry about water in the system that way.

- JimY

I will leave the wheel in place...I have done that before when removing the instrument cluster...

how many hours did it take you jcyhun? that is to pull the dash and replace the pods... my evaporator is fine

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1989 300ce 129k
( facelifted front,updated tail lights, lowered suspension,bilstein sports, lorinser front spoiler, MOMO steering wheel, remus exhaust,stainless steel brake lines). (Gone)

1997 s320 154k (what a ride). Sold with 179k miles. Replaced with Hyundai Equus

1994 e320 Cabriolet 108k



1972 280se 4.5 153k Owned for 12 yrs, sorry I sold it


[/SIGPIC]

I was going to leave the steering wheel in place because I was afraid of the airbag. My brother in law, an MB dealer tech, convinced me that it was very quick and easy to remove the wheel and that it would make things much more accessible. His advice was very helpful. Once I looked at the manual to know the exact order of things, it took only a few minutes to get the wheel the heck out of the way. That sure made the instrument cluster easier to deal with as well as just better general access to everything on the left side.

I did my pods and a heater core replacement last year and it seems like I remember about 15 hours in the whole thing. I did it in the heat of the summer and I opened all four doors and had a high speed squirrel cage fan blowing through the car making it bearable. I also put it on my lift and raised it up just enough where I could easily climb into the seats or could stand next to the car with the dash about armpit high. This gave me the best of both worlds, stand or sit, and kept me from having to stand on my head while working under the dash.

Best of luck with it,

15 hours sounds reasonable. I think it took me about 20, including the evap. replacement.

- JimY

I removed my dash already. I have to go to repair shop to evacuate freon since they charged the system and told me that evaporator needs replacement. I took out blower motor and found a lot of dirt and oily material on evapoator core on left side only. SHowed it to mechanic and he said to change evaporator. But I have a question for guys who did it already. My mechanic told me I have to pull out the whole box then disassemble it and replace evaporator core. Ive tried to pull on heater box with 4 nuts removed as per manual but it didnt move an inch. Do I have to remove the whole box with evaporator,heater core,flaps etc... or I disassemble box in-car. Get to evaporator, and replace it? Thank you in advance

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1999 ML430 Silver 135k ml
Smoked LED taillights, Alpine in-dash DVD player, 12" sub, Pioneer components, 2 amps, 4200k HIDs, ML55 headlights, 20" rims, mirror LED blinkers

SOLD. 1996 E320 145k ml. Burgundy

SOLD but miss it everyday 1992 500sel Black
Chime buzzer mod,Alpine CD/MP3 player with stock amp,Euro headlights,S600 grill,20" rims, BEST CAR EVER!

SOLD. 1990 300E White
187k ml,smoked tails,Euro headlights,17rims,Intake,12" sub in first aid kit,alarm/autostart,buzzer mod

You have to remove the box from the car, don't disassemble it in the car.

There is a fifth attachment underneat the box, near the crash sensor for the airbags. Look in front of where the ashtray used to be.

The box is rather well attached to the firewall by all the sealant (caulk) the factory used. Pry all around it to work it away from the firewall. It takes some time, and it takes some force.

Good luck,

- JimY

thanks. found that bracet in the middle and pryed whole box out. I think Ill replace vacuum pods as well as evaporator.
Thanks for help
Victor

__________________
1999 ML430 Silver 135k ml
Smoked LED taillights, Alpine in-dash DVD player, 12" sub, Pioneer components, 2 amps, 4200k HIDs, ML55 headlights, 20" rims, mirror LED blinkers

SOLD. 1996 E320 145k ml. Burgundy

SOLD but miss it everyday 1992 500sel Black
Chime buzzer mod,Alpine CD/MP3 player with stock amp,Euro headlights,S600 grill,20" rims, BEST CAR EVER!

SOLD. 1990 300E White
187k ml,smoked tails,Euro headlights,17rims,Intake,12" sub in first aid kit,alarm/autostart,buzzer mod

I replaced mine and I believe it took 20+ hours.

One item that I struggled with was disconnecting the air bag. I was trying to disconnect it from the connect on the steering post when I dropped it and it came easily undone from the bag. Looking at it I though that was a permanent connection but the connector easily comes off of that end.