Seat belt mechanism...repair/replace??
 

I've been having a lot of trouble with the "winder" mechanism on both sides of my 74 450SL.Our recent bout of unseasonable cold here in CA has made the problem even worse.It is almost impossible to pull the belt out.It is sticky and wants to move only 1-2 inches at a time before locking up.It can take several minutes battling to get it out(the drill is pull gently,move a bit,retract,pull again, move a bit more etc...).When you do get it all the way out tends not to want to retract either(this issue is worse on the passenger's side)
Is there any way to clean and/or lubricate these??.If the parts were easier to find I'd probably substitute used ones from an SLC.I would think that maybe a closed roof would mean less moisture and debris getting into the car to gum up the winder ...But it's been months since a found a 107 parts car in any of the PNP type yards anywhere around.
I'm also not sure what panels have to come off to gain access,any input on this would be appreciated as well

Seat Belt Mech.
 

The passenger side belt on my 85 380 stopped retracting so removed the plastic panel that covers it and rotated the spring loaded winder which caused it to function properly again. This is probably not a permanent byt it's all got for you. These thigs havean inertia engagement mechanizim but I was unable to find it.

It's unlikely that the seat belt mechanisms from my dearly departed 560SL will work in your car, but they are available and work great. Scroll down to them here - https://sites.google.com/site/mercedesstuff/home

Theory would have it that problems with parts of safety systems should be addressed with new parts.

The belts themselves are in fine condition,but I can see your point re:safety equipment.I doubt these are still available new though.
I am pretty sure the winder mechanisms are just "gummed" up.I was having trouble with the self canceling mechanism on the turn signals and upon removing the switch found it covered in 30+ years of crud.If that much crud can get into the switch through the wheel and rubber cover,I shudder to think how much crud could get into the belt mechanism which has little protection.(especially when going topless)
I'm still not quite sure how to gain access to the winder mechanism though.Will the chrome top plate come off if I remove the retainer/pivot bolt? Or does the entire side/corner panel have to come off as well?

If I can gain access I'll see if mine look like these,but I doubt they will be the same due to the age difference.My car is a 1974 model.

Yeah, that's what I expect too. It wasn't difficult to get at the mechanism. It's pretty obvious once you go at it.

You might be surprised at what is still available new.

Remove that chrome piece on the top of the door post. You'll have a clear view of it then.

Silicone Spray
 

I had a similar problem with the belts on my '81 300TD. I asked my ace tech how hard it is to work on them and he suggested pulling the belt out as far as it goes and spraying the both sides of the belt surface with silicone spray.

Worked like a charm.

I have a set of new Seat belts from a 450 sl if you are interested . These are NOS OEM belts from Mercedes Benz.
Thanks Pete
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