I used a metal oil cap to replace my plastic cap on my 617 Turbo engine, and despite having a new, correct seal it still leaks oil. I also noticed that I can slide it side to side 1/4" or so when it is on and tightened down.

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1979 240D- 316K miles - VGT Turbo, Intercooler, Stick Shift, Many Other Mods - Daily Driver

1982 300SD - 232K miles - Wife's Daily Driver

1986 560SL - Wife's red speed machine

Are you certain that you have a metal OIL cap, and not a gas cap? they are not the same.
the oil cap will lock down with the handle inline with the valve cover.
the gas cap will lock down at an angle...

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

They should be interchangible.

Tom W

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

my metal oil cap say oel on it...

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1984 123.193 372,xxx miles, room for Seven.

1999 Dodge Durango Cummins 4BTAA 47RE 5k lb 4x4 getting 25+mpgs, room for Seven.

The rubber piece under the cap is replaceable, it gets cooked and dried out with heat and age. It`s about $3.00. think Phill has them.

mine will still seep some oil, but if I 180 it, it stays dry.

Mine use to sit an an angle when I first bought the car, then saw some pictires on e-bay of some engine bays and the cap sat straight. at the time I didn`t know I had a gas cap on it.

Then at PNP saw one that had OEL and the star stamped on it, thought it was an old vintge one so grabed it.

Now I find out there is a difference, thanks JIMMY, learn something new every day.

Charlie ☺

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

It came off of a valve cover so I think it is an oil cap. I don't recall the OEL stamp though.

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1979 240D- 316K miles - VGT Turbo, Intercooler, Stick Shift, Many Other Mods - Daily Driver

1982 300SD - 232K miles - Wife's Daily Driver

1986 560SL - Wife's red speed machine

I replaced the metal one on mine with a new plastic one from Park Place Motors as I was losing oil thru the old cap seal. Nice & dry valve cover now and no oil loss.

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Sharing my partner's 2012 Forte 5dr SX til I find my next 123 or 126..
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Do I miss being a service advisor ???

I've used lots of caps. Two different kinds of plastic, and three different kinds of metal ones. If the seal is good, it doesn't leak (on my cars, anyway).

I will second Bgkast's comment, I found two in the yard, tested them and they slide sideways as described. Got new seals, they still slide sideways. They're spring loaded but the plastic ones are too, maybe the metal ones have more yield than the plastic springs (?). Both metal ones I got have "OEL" and have the handle aligned parallel to the valve cover (lengthwise). I tried cleaning the lip where the metal touches the valve cover, still does the same but that solved the leak.

So I'm back to my plastic cap with the warning label on top (not to overfill the engine). I haven't seen a lot of W123's with this labeled cap.

Attached Thumbnails

 

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http://farm8.staticflickr.com/7271/7...144c3fc1dc.jpg

My '85 had that cap.

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1979 240D- 316K miles - VGT Turbo, Intercooler, Stick Shift, Many Other Mods - Daily Driver

1982 300SD - 232K miles - Wife's Daily Driver

1986 560SL - Wife's red speed machine

Well, I can tell you the plastic ones with the thinner handle that sorta resemble the metal ones will fit nicely on the breather/filler on a 54 GMC 270 engine.... Too bad it already had water in the cyl's for the last 15 yrs......DOH!

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Chris
64 190D R.I.P.
80 240D W/617 engine -for sale
82 240D -for sale