A few weeks ago I noticed a new noise that seemed to be coming from the turbo of my '84 300d (a whining chirp when the engine is under heavy throttle on the road). Until now the turbo never made any noise. Looking around under the hood I noticed that there was a threaded hole on the rear of the intake manifold (passenger side, just forward of the banjo bolt) that had less crud on it than other parts. Sure enough, when running, air pumped right out this hole (about 1/4 inch in diameter). Question is: what should be in this hole? Can I just plug it with a bolt or am I missing something important? BTW- car seems to run pretty well without anything in the hole, though I still want to fix it!

I have included a pic to help identify it.

Thanks,

Andrew

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I think that's a bolt hole, but I'll check my '83 in a bit to make sure.

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Whoever said there's nothing more expensive than a cheap Mercedes never had a cheap Jaguar.

83 300D Turbo with manual conversion, early W126 vented front rotors and H4 headlights 400,xxx miles
08 Suzuki GSX-R600 M4 Slip-on 22,xxx miles
88 Jaguar XJS V12 94,xxx miles. Work in progress.

ditto.

plug it with a bolt.

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I love the low-tech fixes. I'll get on the search for a bolt that fits, but if anyone has conformation on the purposae of that hole in the mean time, I'd appreciate it.

Andrew

it may be a test port, such as for boost pressure

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I just looked at mine and the only thing in it is an allen-style plug. The test port idea sounds likely.

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Whoever said there's nothing more expensive than a cheap Mercedes never had a cheap Jaguar.

83 300D Turbo with manual conversion, early W126 vented front rotors and H4 headlights 400,xxx miles
08 Suzuki GSX-R600 M4 Slip-on 22,xxx miles
88 Jaguar XJS V12 94,xxx miles. Work in progress.

just got done replacing my change over valve line off of the banjo bolt right behind this hole you have. it is definitely just plugged with an allen bolt.

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1985 300D - 1984 Euro 280E AMG Clone (SOLD) - 1978 280CE (SOLD) - 1983 300D (SOLD) - 1981 300D (SOLD)

I just went to the hardware store and came back with three possible bolts. The last one fit (standard, fine thread). The noise is now gone and with it, my fears of replacing/rebuilding the turbo.

Thanks for the help!

Andrew

With the Air leaking out of that plug hole your Turbo was over speeding.

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84 300D, 82 Volvo 244Gl Diesel

Doubtful.

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http://superturbodiesel.com/images/sig.04.10.jpg
1995 E420 Schwarz
1995 E300 Weiss
#1987 300D Sturmmachine
#1991 300D Nearly Perfect
#1994 E320 Cabriolet
#1995 E320 Touring
#1985 300D Sedan
OBK #42

The turbo will only turn as fast as the exhaust will spin it. all determined on engine speed.

The hole was just bleeding off pressure that would have gone into the cylinders.

HMMMM, gives me a thought, maybe I can hook up an air horn.

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