Strange speedometer backside

[EeVeeWee]

I got the three meters out of the dashboard, but the backside of the speedometer looks very strange.
Did you ever see this before?

[114015]

EVW,

Wow...; never seen that soo dramatically!

These are the remnants of your speedo's rubber housing,
heavily caked by (excessive) heat.
Usually it should have looked like your rev counter's housing....

These rubber housings can be obtained as aftermarket parts.
I think they are yet NLA from Mercedes.



Achim

[114015]

 

Ooops,
Your whole speedo looks strange. There is a lot of "white" behind the front glass
but not so on the tach counter and the instruments cluster.
What happened to your speedo in the past??
Did someone try to dry out trapped moisture with a heat gun?
Very strange.

Did the speedo still work before you took it out??

Suspicous....


Achim

[ejboyd5]

For want of a proper gasket it look as if someone tried to use expanding foam insulation as a mounting medium.

[mrfatboy]

I can't tell if that's expanding foam or the melted remains of the back rubber cover

[Benz Dr.]

The metal retaining ring is in place and over top of the material that's wadded up. This would lead me to believe that it's part of the original rubber cuff on the back of the gauge but something makes me resist saying so. It just doesn't look right the more I studied it.   

[pj]

Maybe it's obvious to everyone else, but I need to know if you cut the back of the speedometer open or was it like this when you pulled it out?

Regardless of what else might be wrong with this example, it's a fascinating look at the inner workings. I didn't even pull the "gasket" housing off the back of mine... just sent it out to be refurbished and got it back.

[EeVeeWee]

Did the speedo still work before you took it out??

I have no idea, the car wasn't able to drive when I bought it.

[EeVeeWee]

Maybe it's obvious to everyone else, but I need to know if you cut the back of the speedometer open or was it like this when you pulled it out?

Regardless of what else might be wrong with this example, it's a fascinating look at the inner workings. I didn't even pull the "gasket" housing off the back of mine... just sent it out to be refurbished and got it back.

This is what I saw when I took it out.

[merrill]

vintage classics has the part


https://www.authenticclassics.com/230SL-250SL-280SL-Convertible-113-Chassis-s/1.htm?searching=Y&sort=2&cat=1&show=32&page=16