Distributor problem

[mbz.280sl]

My car (1969 280 SL with a 051 distributor) is at the shop for some work. One of the problems I was having was backfiring on acceleration. I installed new plugs and the shop has new points and condensor to install. The shop just called me to say that when they took the distributor cap off there were metal filings inside and the plate that the points attach to seems to be 'loose' or 'unattached' (words from the shop). I'm not a mechanic and I'm not at the shop but I told them I would ask a question here to see if anyone understands what the problem is. Is there something missing or broken inside the distributor?

[Naj ✝︎]

Have a look at the distributor in the wiki.

There is an exploded diagram which might help to identify what parts are damaged.

http://www.sl113.org/wiki/pmwiki.php?n=Electrical.Distributor

naj

[mbz.280sl]

Thanks, Naj,

I printed out several pages and took them to the shop.
Hopefully this will help them fix the problem, whatever it is.

[Cees Klumper]

Could be that the vacuum pod that sits on the side of the distributor, and has a thin 'arm' that goes into the distributor and attaches to the plate (in order to be able to do its advancing thing) has come loose. Sounds like they need to take it out and inspect it thoroughly.
Dan Caron (Dr Benz) is the best available source to have it rebuilt, which is what it sounds like it needs ...