1980 SLC380 Front Seats back restraints/locking mechanisms

[MB380SLC]

Small problem to resolve. Front seats back restraints are not working. Mechanism is air operated with two sets of diaphrams on either side of each front seat connected to locking mechanism (mechanical) and tubing where air is sucked out (by what I can't fathom) to operate the diaphrams. System apparently should engage when the engine is running. Don't have a manual in order to trace fault so would appreciate some help here. Thanks

 

[Myros]

I think they are run from engine vacuum

and should only lock if the doors are closed, otherwise you wouldn't be able to offload passengers.
Give me a day or to scare up what i can, i'm away from my manuals and references at the moment.
Malcolm might have it all to hand though, he usually does.

 

[MB380SLC]

thanks for prompt interim reply. Look forward to fuller explanation when you have a moment. Per chance could the central locking mechanism also be air pressured, because that also isn't working?

 

[television]

Your car has a vacuum pump that locks all of the doors and seats,, I have tried to put up details for you, but the site is down this morning, I will come back to it

 

[Myros]

Malcolm to the rescue again

I think the only other thing that is vacuum-operated are the headlight aim-adjusters and the heater controls. If they aren't working as well then you have a vacuum supply problem at source, rather than at consumer. there are some spheres for storing vacuum under the right wing, ahead of the wheel. Start checking from there to see if they are punctured or connectors have perished or come off, and work your way back.

 

[MB380SLC]

Thanks Malcolm. That would make sense, so look forward to finding out further details as to its location and fixing problem in due course.

 

[MB380SLC]

Thanks Myros. The headlights are adjusted manually with a screwing mechanism at front. The heater works fine. But the vacuum spheres under the front right wing is a good lead (always wondered what that was for, besides causing some damage to bodywork with front wheel pushing it up against wheel arch wing ) so will tackle that.