Racing,

Very difficult to get a photo, but there is a sleeve like thing on the shaft snout behind the Woodruff key. It isn't black, though. I also wanted to point out the two piece thing seems to be intentionally a two piece thing. The inner part has a slot for the Woodruff key and the outer half doesn't.

I will get some part numbers and start searching, but if you have never seen them I am really wondering what they are. I hope I can find a brand if it isn't an MB part.

The tensioner plunger has a snap ring that is supposed to engage a groove in the cylinder to prevent it from coming out all the way. When we got it out, the snap ring was all that was holding the plunger inside the cylinder. I think the new style ratcheting chain tensioner is needed. They are wildly expensive here though.

I think most of this damage had been a result of the last maybe 3,000 miles as we adjusted the valves in March and only the exhaust valves needed to be adjusted. So, we spent a lot of time peering in and around the chain tensioning rail at that time and while I cannot say I recall examining the chain and the tensioning rail then, I am also fairly certain that the visible damage we saw this time when we took the valve cover off would not have been overlooked. The oil was changed at that time, before the trip back to West Lafayette, Indiana (about 900 miles) and then again before returning due to the gas contamination.

Well, off to set up for the cover removal. Thanks for the hints on the bolt hiding in the gunk. Some parts of this engine are sparkling clean, while others are filthy. The area around the bracket is filthy. Wonderful.

Jim

__________________
Own:
1986 Euro 190E 2.3-16 (291,000 miles),
1998 E300D TurboDiesel, 231,000 miles -purchased with 45,000,
1988 300E 5-speed 252,000 miles,
1983 240D 4-speed, purchased w/136,000, now with 222,000 miles.
2009 ML320CDI Bluetec, 89,000 miles

Owned:
1971 220D (250,000 miles plus, sold to father-in-law),
1975 240D (245,000 miles - died of body rot),
1991 350SD (176,560 miles, weakest Benz I have owned),
1999 C230 Sport (45,400 miles),
1982 240D (321,000 miles, put to sleep)