W124 Dash Removal and Climate Control Pod Replacement - PeachParts Mercedes-Benz Forum

Jeremy5848 · #1 07-06-2009, 02:35 PM

1987 300D Turbo, W124, OM603, build date July 1986.

Pardon the length but there's a lot of information that's nice to have before starting this job. For those who don't like reading long posts, just look at the pictures.

The purpose of this work was to
1. Replace the car's badly cracked dash with a new-to-me, black-painted-blue, crack-free dash from an '89 300E. SEM Color Coat #15043 "Shadow Blue" is a near-perfect match for the dark "navy" blue of the original Mercedes vinyl used in the W123 and W124 (and W201?) cars.
2. Replace the 7 climate control vacuum pods with new ones (all of mine were bad except for one of the two foot-well pods). Later models have only a single foot-well pod; my early W124 has two.
3. Do some preliminary work (running cables, etc.) for a 3-gauge panel (voltmeter, turbo boost, EGT) to go in place of the ashtray.

Rather than repeating what others have written, I'll simply note things that I ran across that were different, unusual, or troublesome. Some of my pods were "bad" in that they had pinhole leaks; they probably worked after a fashion. Others were completely ripped and must have put quite a load on the vacuum system when the PBU called for them. In a recent post on one of my threads, "al b" noted that his SD shifted better after he replaced pods in his car, presumably removing some vacuum leaks. I'll be interested to see what happens in my car.

If you have an opportunity to visit a junkyard (whether you are planning to replace your dash or re-use your original) be sure to find a similar car and grab every piece of dash hardware (screws, clips, brackets, etc.) you can find. All of it is expensive and some of it is unique, not hardware store stuff. If you're replacing your dash with a new one, be sure to strip every bit of hardware before tossing the old one.

Jim Y's post of a couple of years ago "W124 Climate Control -- Vents" is really useful for keeping track of which vacuum line goes from which port on the vacuum block to which pod and what colors all the lines are. I used it to make notes on the pods as I tested them and later as I did the replacement work.

I found three brackets in my car attaching the dash to the frame that weren't in Babymog's 12-30-2007 thread "124 Dash Removal Tutorial (sans photos)." Possibly these brackets were eliminated in later years. One bracket, on the left side of the dash, shows in EPC as part 124 689 03 14 "no longer available." The other bracket is on both right and left sides; I can't find it in EPC.

The edge of the dashboard (where it meets the bottom of the windshield has a piece of fabric sewn along it, possibly to prevent squeaks. My replacement dash had this piece but it was rotten so I stripped it off (made the dash easier to paint). I could have taken my chances without but my wife came up with a length of edging that she uses in her sewing. Contact cement worked great for gluing the edging to the dash.

While you have the dash out, vacuum and wipe the edge of the frame next to the lower edge of the windshield and wash the inside of the windshield. You may never get another opportunity to clean this part of the car.

I had previously replaced the dome light assembly with a later version that has a lighted sunroof switch. With everything apart, I was able to run a wire down the passenger's A-pillar to the light in the passenger vent control so that the sunroof switch will illuminate along with all of the other switches. (Previously it had been wired so that the switch was illuminated whenever the ignition was turned on.)

As I removed various items, I put the related fasteners in a small zip-lock bag and taped it to the item. Things that could be confused for other things also got an identifying tag (old business cards work great for this purpose).

Where parts are hard to reach and could be dropped into the void, I used an extendable magnet (auto parts store) along with my tool. As soon as the fastener came loose, it was captured by the magnet.

I wore an LED headlamp for almost every operation. Made a lot of things easier to see. For illuminating the work area after dash removal, try to suspend a shop light over the windshield outside of the car. If you are outside, the sun also makes a good work light but I was in the garage.

If you are replacing all of the a/c vacuum pods, there's an order to be followed since some are otherwise in the way of others.
1) Remove the airbox top along with its attached diverter pod. (See Sixto's "87 300D diverter pod replacement" thread dated 02-21-2009.) Note that of the four little clips at the front, only the two inner ones need to be removed. I dropped one, of course and never did find it. Elsewhere someone has posted part number 201-835-01-34 for that part, which I confirmed in EPC as "Spring, heater case."

NOTE: The Phillips screws in the airbox top that Sixto cursed (especially the two hidden next to the firewall) are indeed hard to extract. However, once you have them out, replace them with the screws that hold the instrument cluster together (get 'em from a junkyard or a dealer). They are almost exactly the same size and have a 6mm hex head in addition to Phillips cross slots. It is much easier to operate on these screws with a small socket set than with a screwdriver. Don't get enthusiastic and strip the plastic.

2) Next, remove the defrost pod on the right side.

3) Now you can get at the pair of recirculation pods that live at the back of the airbox. Remember Sixto's recommendation (in his thread "87 300D recirc and defrost pod replacement" dated 02-28-2009) to first remove the "bracket that holds the vehicle speed sensor distribution block and some relays." The 10mm nut back at the firewall is particularly easy to drop into the bowels of the dash so use the magnet alongside your socket set.

4) The footwell pod(s) can be done at any stage of the game. They're the only ones that can be done without pulling the dash. Later 124's with a single rectangular pod are much easier than the early ones (like mine) that have two little round pods. These round pods are attached with three clips like the diverter pod but are harder to get at. I suspect that it is necessary to pull the console to really get at them but I don't know how to do that. Instead, I ignored the left pod, which was good anyway, and fixed only the right pod. To do that, I took the pod apart without removing it. There's enough room to reach in and unclip the back of the pod, leaving the front attached to the airbox on a bracket. Then I was able to release the footwell door from the pod's arm and pull the diaphragm out of the pod. I took my new pod apart, stole its diaphragm, and used it to put the pod on the car back together.

5) While replacing the center vent pod (lives in the airbox, see Sixto's thread "87 300D center vent pod replacement" dated 02-21-2009) I discovered that the plastic clip (or "pin") that holds the actuating arm to the air door was missing. Even if that pod had been good, it wouldn't have done anything! I found a replacement clip in my junkbox. I could have used a screw and a locking nut or a cotter pin -- almost anything will do as long as it stays put. Note that the center vent pod is one of the few that can be rebuilt.

When reassembling the dash, note that the lower sections are held to the dash by sheet-metal screws and nuts. The sheet-metal nuts can slip out of alignment if you're not careful. It hurts to get all but one screwed in and then discover that the last nut has been knocked off.

After inserting the right side vent, remember to push the air hose onto the vent before putting the glove box together.

It's finished -- it looks good and works great -- thanks to all who posted DIY threads on this subject, especially Babymog (dash removal), gsxr (pod replacement), and Sixto (pod replacement).

Jeremy

pwogaman · #2 07-06-2009, 03:48 PM

Great write-up and pictures!

lrg · #3 07-06-2009, 04:02 PM

Great write-up! One additional piece of advice (that I wish I had done) is to shoot some compressed air on the heater/evap coils from the inside out to clean them out. Early cars like mine don't have pollen filters so these can get pretty dirty and lose efficency. You can do it from the fan side but you'll be blowing the dirt deeper into the HVAC system in the process.

dagObx · #4 07-06-2009, 05:41 PM

Super write-up, especially the photos! Now I have some guidance to do the pods on my 87 300D

Much Graz!

KeninMorganHill · #5 07-14-2009, 07:07 PM

Great write-up and pics.

I just did this last Friday and was first very intimidated by it, BUT.. once I dug in and did it very carefully, it actually turned out not to be so bad. "Just very involved."

The only bits of advice I would also thrown into the mix as well, is to drill-out the two (2) rivets holding the internal pod and bracket located inside of the box itself. I replaced these with two screws, lock washers and nuts.

I did this mainly because it was pretty hard to push down and turn the pod at the same time. By going this route, all I need to do next time around is to undo the screws and pop the whole assembly (Pod and Bracket) out as one unit and replace accordingly.

I would also recommend replacing all of your little dash bulbs as well. It's alot easier to do it as this point, then to have to dig each and every one of them out later.

From what I saw, there had to be be about 13 or 14 of them.

"Good luck everyone!" It can be done. :-)

- Ken

misterlou · #6 12-13-2017, 10:32 AM

Going to use this amazing posting from 2009 as my guide. Getting some Photobucket alert that is blocking the photos that @Jeremy5848 posted. Argh!

dieseldiehard · #7 12-13-2017, 01:42 PM

Quote:

Originally Posted by misterlou

Going to use this amazing posting from 2009 as my guide. Getting some Photobucket alert that is blocking the photos that @Jeremy5848 posted. Argh!

That blocking is a major shift in Photobucket's previously free hosting of pics, so links now are dead. Unless they get paid, it seems like Ransome to me!
Here's a story about it, there are many out there I am sure its just the first I saw when I did a quick search for Photobucket on the Inet:
Photobucket addresses complaints over new policy that charges heavy users $400

SD Blue · #8 12-13-2017, 04:29 PM

I believe someone has found a fix for this. I haven't tried it myself.

Do a search for "solution photobucket images"