Vacuum Symptoms on 87 300TD

[shertex]

Today I'm picking up a 1987 300TD. I think I'm getting a pretty good deal, in part because the owner has messed up the vacuum connections and just doesn't want to deal with it anymore. In short, he knew he had a vacuum problem, tried disconnecting and connecting things without having any idea what he was doing , and now can't figure out how to restore the original configuration.

Car wouldn't shut off, so he knew he had some sort of a vacuum problem.

Fiddled with the vacuum hoses, then car would shut off but tranny shifting was messed up.

Fiddled with it again, tranny and shut off back to normal, but now the engine dies after a little while.

I'm assuming that, armed with a vacuum diagram, it shouldn't be too difficult to sort out. But I imagine what he's done is now hooked up the wrong vacuum line to the shutoff valve. Does that sound likely?

It has 260,000 on it but only 100,000 on the engine. And no rust. Interior is good except for the front seats. Paint is decent. AC doesn't work. Two windows won't go down. So it will be a good project car for me....then I'll sell it to one of you guys.

[vstech]

should be pretty simple fix, take a good pic of the vacuum lines on your bay, and I'll compare to mine, and tell you what goes where.

[Jeremy5848]

And be careful with any vacuum diagrams you happen to be offered. When I had an '87 300D Turbo I collected every one I could find. They were all a little different and none exactly matched my car, which no doubt had been boogered by a PO. I did manage to get the car running properly and I'm sure you will too.

Having a second car alongside for comparison is ideal but vstech's offer is good too. The pix he will want to see are of the IP/ALDA/VCV area, the Blue Flying Saucer area, and the vacuum pump area. I presume you'll want to remove the EGR plumbing and that will help simplify the mess. There's a whole boxfull of stuff behind the right headlamp that can be removed.

Jeremy

[auspumpen]

[sixto]

Do you really need the vacuum reservoir? Mine was disconnected for a while (BFS removed) and I didn't notice a difference.

Sixto
87 300D

[shertex]

Thanks, guys....looking forward to figuring this out.

[auspumpen]

Originally Posted by sixto

Do you really need the vacuum reservoir? Mine was disconnected for a while (BFS removed) and I didn't notice a difference.

Sixto
87 300D

That's a good question. I've kept them in my cars, but I haven't really tested how vacuum consumers respond to the absence of residual vacuum.

[shertex]

I think what I want to do is get it back to the stock arrangement....then think about modifications. I'll definitely remove the ALDA.

[sixto]

No, you want to get it running Seriously, the vacuum circuits are independent other than sharing a source. You can isolate one system to get it working then work on the next.

Sixto
87 300D

[shertex]

Originally Posted by sixto

No, you want to get it running Seriously, the vacuum circuits are independent other than sharing a source. You can isolate one system to get it working then work on the next.

Sixto
87 300D

So, for example, I could eliminate everything on the passenger side of the engine bay, plugging the source, and just try to get the rest right, correct?

[Jeremy5848]

Yes, everything on the passenger side is for EGR/ARV, which you will want to eliminate anyway. You can disconnect and plug those lines, thus eliminating any vacuum leaks that might exist on the passenger side.

[shertex]

This morning I wasn't even able to get the car running. Am I correct to assume that no vacuum configuration, no matter how miswired, should be prevent a diesel from starting?

[vstech]

no not correct.
if you have vacuum directly routed to the shutoff, you will never get the motor to start.
is the shutoff lever up or down?

[shertex]

Originally Posted by vstech

no not correct.
if you have vacuum directly routed to the shutoff, you will never get the motor to start.
is the shutoff lever up or down?

I removed the hose from the shutoff. When the engine WAS running, I applied vacuum to the shutoff with a Mityvac and it immediately shut off. One odd thing I noticed when the engine was running is that the shutoff lever seemed to be bobbing up and down. Does that tell me anything?

[vstech]

yeah. it tells you there is a vacuum problem, or a shutoff valve problem. it should NOT move. does the handle bob with the vacuum line disconnected?