Just finished an engine swap. New engine will not shut off by the key. Assume it is a vacuum issue. Thoughts? Thanks.

__________________
1974 450SL White/Navy Blue

1983 300SD White/Parchment, VDO Boost Guage, 215/60R15 Bridgestone Potenza RE960AS Pole Positions on 15X7 15 Hole Wheels, Straight Piped, 298K?

2004 Ford Excursion XLT 4X4, 5.4L V8, 285/65R16 BFG AT KO

vacuum goes to your ignition lock and from there it goes to the vacuum shutoff solenoid on the injection pump.


get a mityvac and check everything etc...

Did the engine that was swapped in stop running when the key was turned off? Did the vehicle before pulling the engine shut off when the key was turned off?
If yes to both of them, then during the swap a vacuum line was cracked somewhere. Very easy to do on a 35 year old vehicle.

Yes to both.

__________________
1974 450SL White/Navy Blue

1983 300SD White/Parchment, VDO Boost Guage, 215/60R15 Bridgestone Potenza RE960AS Pole Positions on 15X7 15 Hole Wheels, Straight Piped, 298K?

2004 Ford Excursion XLT 4X4, 5.4L V8, 285/65R16 BFG AT KO

Using a Mityvac vacuum pump apply vacuum to the shut off valve located on the injection pump. If the engine turns off you have a lack of vacuum to the ignition switch or a broken/cracked vacuum line in the shut off system.

Does anyone have a vacuum diagram for the turbo 617? Might have mixed up my tubing.

__________________
1974 450SL White/Navy Blue

1983 300SD White/Parchment, VDO Boost Guage, 215/60R15 Bridgestone Potenza RE960AS Pole Positions on 15X7 15 Hole Wheels, Straight Piped, 298K?

2004 Ford Excursion XLT 4X4, 5.4L V8, 285/65R16 BFG AT KO

U put new rubber connectors on all the tubes right?

Because a lot of times it's just the connection is loose on the brown tube to the shut of solenoid.

__________________

On W123's the 84-85s California versions have amore extensive vacuum system.
This is a diagram of the one on my federal 84 300d.

Attached Thumbnails

   

__________________
84 300D, 82 Volvo 244Gl Diesel

Thanks.

__________________
1974 450SL White/Navy Blue

1983 300SD White/Parchment, VDO Boost Guage, 215/60R15 Bridgestone Potenza RE960AS Pole Positions on 15X7 15 Hole Wheels, Straight Piped, 298K?

2004 Ford Excursion XLT 4X4, 5.4L V8, 285/65R16 BFG AT KO

are people still asking about this ****??

Search and you shall find!

__________________
Rindfleischetikettierungsüberwachungsaufgabenübertragungsgesetz

Oh well, yes they are. And I just did a search and found this thread, from a link that D911 put up on another thread.

I haven't put in that much time with my 300D yet. Just did the first long trip with it since about Feb. 2020 and my doddering vacuum system went fully tits up in the process. The ignition shut off has no effect on the engine.

I just moved and couldn't find my Mityvac before I left. I wanted to hook it to the proper vacuum line at the ignition so as to shut it off w/o opening the hood. Did that once before. Lately I have needed to use the underhood lever about 1/3 of the time. On other occasions it would shut off with the key but take about 10 to 20 seconds.

Something slightly broken went full on broke day before yesterday. Previously it would act like it was going to shut off at some point, now you can run all day with the key off with no sign of anything wrong. I'm going to be visiting a few people I want to make a reasonably good impression on and needing to open the hood to shut off the engine is perhaps not best. 'Oh look, cmac's old car is more eccentric than he is.'

I found the lower priced plastic body Mityvac MV8000 at O'Reilly's for $53. Amazon has it for around $34, and the better MV8500 for $69.

I'm in OlyWA, not in a next day delivery Amazon Prime area - order on Sunday, would get it Wednesday so I paid O'Reilly's price.

I couldn't recall which line wanted the vaccuum, I hooked it up first to the all brown - would not shut off or hold vacuum. Hmmm ...

I hooked it next to the brown with blue and it shut off nicely.

The no hold vacuum thing on the other line could be an excellent bit of info. My brake boost is not great and I see from D911's image that the lines are closely related. I'll examine that line more tomorrow.

__________________
Te futueo et caballum tuum

1986 300SDL, 362K
1984 300D, 138K

Not sure on which you decided (plastic or metal), but the plastic one works just fine. Assuming it's well cared for, it will last decades. I bought mine sometime in the '70's and she's still goin strong. I think I paid about $25, waaaay back then, so it hasn't really gone up that much in price IMHO.
Wanted to ask what you meant by "my brake booster is not great"? If there's a leak, associated with that, probably not helping anything (as you probably know). Wanted to mention the small o-ring between the master cylinder and vacuum booster. My 240D's brakes were "not great" either, until I found that o-ring completely missing and replaced it. Easy job, don't have to open the system.
Just one more observation. If you're concerned, in the slightest, about what anyone thinks about the car you're driving, a 40 year old diesel MB is probably not your best choice (unless, of course, it's a mint condition cream puff). Even at that, most people just don't "get it" about these cars....no matter what. Cheers!

In my experience if the two lines are hooked up backwards going to the
vacuum switch in the key switch, the shutoff won't work.

The fact that it's a 40 year old diesel doesn't worry me, or what people think about that - I was more concerned with the business of needing to open the hood every time to shut it off. Doesn't look too well together.

My brakes are about as hard to use as when the engine dies and you have to come to a stop. Much pressure required. I feel safe enough, I know what to expect. But I really should make it better somehow. Thanks for the O ring tip - I'll check it out.

I got the plastic Mityvac. It's all they had on the shelf. Seems good enough.

__________________
Te futueo et caballum tuum

1986 300SDL, 362K
1984 300D, 138K

With all the lines plugged, excluding the brake booster, what is your vacuum reading with the engine running?

__________________
“Whatever story you're telling, it will be more interesting if, at the end you add, "and then everything burst into flames.”
― Brian P. Cleary, You Oughta Know By Now