OK, I have the turbo "snorkel" on tight and have replaced the leaky, dry-rotted old fuel return hoses on my '83 300D with the '85 engine. But now she's started "dieseling" at shutoff. (Did it a time or two before I replaced the hoses and has done it once since.

There still seems to be some fuel leaking at each cylinder around the seam between the glow plugs and the head.

Anyway, the dieseling seems to happen when the car has been started cold and driven only a short distance, maybe two to five minutes. Then when you switch off the key, the engine doesn't stop without opening the hood and pushing the kill spot on the linkage. ... If the car is warm, the engine has died at switch-off every time so far.

What's the first thing to check?

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-- 1983 300D, acquired 10/19/2005 at 215,000+ turbodiesel miles ... engine croaked almost immediately ... back on the road at 217,210 with a 144K turbo motor from a donor '85. ... May 2007, replaced radiator. ... Now (2/28/08) about 240K miles and dead due to battery?

well perhaps a vacuum leak is to blame.. when the lines get warm(vac lines) they swell up a lil and will probably seal very well and when cold and not warm they let a lil vac out.. how well do your door locks work?

Glenn,

Fuel leak is probably he injector fuel return lines. If that's the ones U replaced, Maybe they aren't on tight. Try putting some engine oil in the hoses before U push them on the nipples.

U probably have a vacuum leak. After the engine is run long enough it makes enough vacuum to shut itself off.

So check the vacuum at the brown vacuum line going to the IP shut off. Check it both hot and cold. If the shutoff device is working, U should be able to shut off the engine by sucking on the vacuum line with yout mouth. If U have a mityvac, that will work better.

P E H

Yup.

I bet you have some cracked, leaky vacuum hose/connectors under the hood. If I were you I would search for any old-looking hose and replace it, then see if the problem persists. Make sure everything is well-connected, too. If that doesn't solve the problem then I would start checking elements like the IP shutoff valve.

If it wasn't under the hood, the engine heat wouldn't make a difference leak-wise. I know this because I have a leak in my climate control system and the engine heat doesn't effect it at all, but if the ambient temp. is high enough the leak disappears.

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Ralph

1985 300D Turbo, CA model
248,650 miles and counting...

Thanks for the input.

The door locks work fine when the engine's running, but a few minutes after you shut it off then they don't. Or at least didn't before the engine was changed. I haven't had any passengers since to notice if the locks come up when I open the driver's door or if they wait to come up until I start the engine.

I think there's a little vac leak at a place where the mechanic patched two small vacuum lines of some sort into a bigger line, apparently by punching little holes in the big line and then pasting or rubber-sealer-ing the little lines so they'd stay in place. ... I can pull one of them right out and stick it back in, so if it's that easily dislodged it might be leaking around the hole.

As for the injector leaks, I did replace the fuel return hose and unless it's leaking right around the neck of each hose then the leak is elsewhere. Before, the hoses were dry-rotted and cracked from end to end, and the fuel was seeping through the braided cloth all down the length of every hose. ... Now I just have pooled diesel fuel around each glow plug after the car has been started and run for awhile.

I will try removing each line and oiling it a bit and putting it back on to see if that helps.

Again, thanks!

__________________
-- 1983 300D, acquired 10/19/2005 at 215,000+ turbodiesel miles ... engine croaked almost immediately ... back on the road at 217,210 with a 144K turbo motor from a donor '85. ... May 2007, replaced radiator. ... Now (2/28/08) about 240K miles and dead due to battery?

Glenn,

There is a a reserve vacuum tank that is supposed to hold vacuum after the engine is shut off. So U have a slow leak that is draining the reserve tank and when the vacuum pump starts working with the engine running your vacuum devices start to work again.

U have to find the vacuum leak which isn't always easy. That will fix your problem.

P E H