Bosch 051 distributor collar

[Bob G ✝︎]

Well I finally aquired the right distributor for my 1968 280/SL from Benz Barn and it looks great. Now I can throw the old 009 in the trash. What bothers me is, it seems that some parts are missing  where the distributor fits into for ajustment. I call it a collar.

There is one bolt in the very back of the distributor that holds it in place in the locked position. It is very hard to access. You can burn your hand trying to adjust the distributor to set the dwell and timing on the radiator.

I have looked at many other 280SLs and it looks like there are several different clamping types that may have been used throughout the years. Can someone comment on this and provide me with pictures of how this clamping unit or collar should fit and what I should use for my Bosch 051 distributor for my year SL.

Will be very appreciative.

Bob Geco

[TheEngineer]

I have both distributors, the 051 and the 009. I'm using the same collar. The clamping screw is hard to get at and I have turned the collar around: Bottom side up. That way the clamping screw faces the radiator and I can get my hands in there. Working on the distributor is much easier with the hood removed. There is nothing wrong with the 009 distributor: Don't throw it away. It costs $1,640 new. MB number is 0 002 158 38 01 and it is the regular replacement for the 051 which is no longer available. Call Bosch at 888 667-1042. If you need a pix, I'll try.

[TheEngineer]

Here is the pix as promised: I couln't get my eyes in there, but the camera did just fine. Please observe that I'm running the 009 distributor. The car runs best with it.

[George Davis]

On my car the clamp screw is on the valve cover side of the distributor, with the screw head facing to the rear.  Access is easy using a long, t-handle allen wrench (5 mm, I think).

forgot small point: the allen wrench has a ball end so it works at an angle

George Davis
'69 280 SL Euro manual

[Benz Dr.]

The clamp is more a part of the housing that the distributor sits in. There are at least 3 basic types.
1) has a pointer and a graduated scale for fine adjustments.
2) similar to above but it won't have a pointer and only has a small amount of adjustment. Both types have an allen screw on the clamping collar for large adjustments.
3) as shown in the picture above. This is the last version and may be stock in ' 71.

Daniel G Caron

[tuultyme]

My clamping collar has been striped out as there is a nut on the end of the allen bolt to tighten it up.  Are the different types available as replacements?

Bruce; 268Blaugrun(green) 1970 280SL; IL

[TheEngineer]

Three ways to fix your stripped thread: 1.Install a heli coil. 2. Put a nut on the end and tack weld the nut to the collar in two places, just to secure it against rotation (small tacks using TIG) 3. just install a nut and hold it while tightening the screw.

[Cees Klumper]

I should have a couple of these collars, and of various types, lying around if anyone's interested. Just send me an email and I'll check.

Cees Klumper in Amsterdam
'69 white 280 SL automatic