Help with heater matrix valve lever, 280 SL - what an idiot I have been!

[PeterW113]

Hello all,

I have partially dismantled the dash board in order to replace the heater controls levers as the plastic levers have lost their strength and do operate efficiently.  The problem also involved the Heater Matrix control lever which had jammed. I have now managed to free this and it works properly. I have attached a picture of the said lever to show this, which I came across on the forum so I hope the member who took it doesn't mind me using it.

My problem is
1) the lever on my car is bent.
2....and this is where I have been an idiot is that, I have managed to drop the lever inside the heater matrix housing!!!!

This is my dilemma;
1) Do I have to remove the rest of the heater matrix to retrieve the lever and if so how involved is it?
2) Bearing in mind it is bent is it possible to source a new lever?

So far I have tried the SLS website and the lever is not listed so I am not sure how easy it would be to get a replacement.

To add to the whole picture other jobs on my list would seem to make sense to consider at this time are:

1) All the instrument lights have stopped working and it does not appear to be the fuse.
2) My odometer / milometer has worked lose (I found one of the knurled securing nuts on the floor) and getting access to the back seems impossible  in order to screw it back on. Oh and one last thing, the unit makes a mild throbbing noise at low speed, say below 40mph as the speed indicator needle waves around. Above this speed it seems fine.

Sorry to hit you with such a list but I thought I should explain the bigger picture though the problem is with the bent but missing heater matrix lever.

Your help as ever is much appreciated.

Regards

Peter

[PeterW113]

To all,

I have just come across the very article I should have read before I started in the Technical manual, but my dilemma still remains, is it possible to get a new lever or do I have to start a major dismantling procedure and retrieve the old one.?

Regards

Peter

[George Des]

I have never seen any of the usual sources list this as a replacemnt part, but you can always try. My guess is that it came as an integral part of the heater matrix and valve assembly. You may be able to find a good used one from one of the board members. If you can't, the other alternative like you say is to pull the heater assembly apart to retrieve your part and perhaps straighten it out. It is supposed to have a bend in it--what I would be more concerned about is the square slot that is cut in it--if this becomes rounded off it will not engage with the valve properly. If too far gone, you may be able to fabricate on using the old as a guide. Whatever you do, do not lose the small tab that fits under the lever in the slot. The matrix disassembly is one nasty job that has almost become a "right of passage" for anyone dealing with our cars. Lots of info in the forum on how to go about it.

George

[Larry & Norma]

It is difficult to visualise where the lever might have got to, if you have to take the matrix out
then it is quite a game but I have done it. If the bracket on the end of the matrix has broken
you can get this resoldered at the same time. Start by taking the tacho out....
To tighten the speedo you must take out the tacho and centre guages. Easier if you remove the steering wheel
and maybe seat. You have to reach up behind the dash working blind mostly whilst
standing on your head. Lots of swearing involved. But it can be done.
The noise I would guess is the cable on the way out. Yet more fun.
The light thing is probably the rheostat, search and you will find a way to bypass this, again
tacho out to get to it........
Not much help i'm afaid but can all be done

[PeterW113]

George & Gnuface

Good news, I have managed to retrieve the control lever using an extendible magnet, phew! as I was not looking forward to pulling the matrix. I have added a few pics of the lever, as you can see the interface cut out looks square which is good but rest of the assembly still looks a little bent, I will carefully try and straighten it a little.

Thanks for the advice about removing the tacho to get to the speedo, I will try that.

Many thanks to you both of you for your help.

Peter

[Benz Dr.]

I bend them back into shape so that the valve will always shut off completely. I pay attention to having it shut off so that no hot air enters the cabin. There may be times when you want heat but not during the summer on a hot day.

The linkage that moves this lever should be removed if you can and lubricated so that it will not bind. We have been using liquid silicone on the water tap which makes it move very easily. I was using high temp grease ( disc brake grease ) which worked OK but nothing like the way silicone works.