300SD with an engine from a 300TD station wagon, OM617.952 with the rear suspension pump plugged. It was transplanted into a 300D like this and ran till the transmission died, then it was removed and a few months later I picked it up. 150,000 miles, ran on VO for a few thousand. It reportedly ran strong the whole time.

The previous engine had a slipped cylinder sleeve and a new(er) engine was the cheapest fix. See thread here.

But now it won't run very well. It is a pain to get it started, took several tries to get it going. It leaks like crazy out of one of the injectors and out of the hard line connection to the IP. Once it was running it seemed to idle OK, if a little low, but would not rev past 1000 rpm. Throttle response for the 250 rpm that it existed was pretty good, around what it used to be with the old engine. After a few minutes of running and making the video it stalled while idling. I have replaced filters and checked to make sure the throttle linkage is fully engaging the injection pump. I also tried running it from an external tank.

One strange detail about this car, It was a Montana State University senior design project as an SVO conversion. It draws diesel from a 7 gallon tank in the trunk, SVO from the main tank (although this hasn't been done yet). The return is looped on both the diesel and the SVO. The system has been installed but not tested yet, although it seemed to be running just fine on diesel with a blown head gasket on the old engine before the swap. I set it up to draw and return to a 2 gallon gas can under the hood to see if this system was the problem, but couldn't even get it started.

The primer pump for the fuel system leaks like crazy, but seems to still work well enough.

Here's a youtube video after I got it started:
http://www.youtube.com/watch?v=biiidzR4VnE

Anyone seen this before?

RePlace it ...When they leak they also allow the mechanical fuel pump to suck
air along with fuel.That's the cause of the starting difficulties.And also may
be why it's having acceleration difficulties.


AND... oh,Yeah looks like #3 has a leaking delivery valve o-ring(Maybe).There
is also something "binding" in your fuel control linkage under the hood.
On second viewing...The fuel control linkage is not properly connected!
The STOP lever you're pulling on to try and get some RPMs.That ain't right!

__________________
'84 300SD sold
124.128

That's what I was thinking.

__________________
1985 500SL Euro w/ AMG bits 130k
1984 300SD Turbodiesel 192k
1980 240D Stick China 188k
2001 CLK55 AMG 101k
2007 S600 Biturbo 149k Overheated Project, IT'S ALIVE!!!

Is the linkage really totally wrong? I though pushing on the stop lever shut it down. . . but I don't have any experience doing that.

Anyway, here's some pictures of the linkage. I'm ordering a new primer pump tomorrow. I REALLY hope that's it. . .




LINK to others

The linkage looks right to me.....is there much play in it? Does the link to the injection pump move all the way down to the load stop when you press the accelerator pedal? If the linkage isn't moving the link to the pump isn't moving then its not going to rev up properly.

__________________
-diesel is not just a fuel, its a way of life-
'15 GLK250 Bluetec 118k - mine - (OC-123,800)
'17 Metris(VITO!) - 37k - wifes (OC-41k)
'09 Sprinter 3500 Winnebago View - 62k (OC - 67k)
'13 ML350 Bluetec - 95k - dad's (OC-98k)
'01 SL500 - 103k(km) - dad's (OC-110,000km)
'16 E400 4matic Sedan - 148k - Brothers (OC-155k)

It hits the stops on the injection pump.

Linkage seems fine, has less slop then the old engine's did. I'm ordering a new primer pump, could that really be letting enough air in to make it run this poorly?

Its possible, how does it run while idling? Can you see any air bubbles in the lines going to the injection pump?

__________________
-diesel is not just a fuel, its a way of life-
'15 GLK250 Bluetec 118k - mine - (OC-123,800)
'17 Metris(VITO!) - 37k - wifes (OC-41k)
'09 Sprinter 3500 Winnebago View - 62k (OC - 67k)
'13 ML350 Bluetec - 95k - dad's (OC-98k)
'01 SL500 - 103k(km) - dad's (OC-110,000km)
'16 E400 4matic Sedan - 148k - Brothers (OC-155k)

Made some progress today.

I did notice that the black vacuum line coming from the black box on the top of the engine (switchover valve?) isn't connected to anything at the T. I reconnected it to the vacuum control valve. Don't know if this fixed anything.

I also noticed that the throttle linkage is missing a C clip where the rotating shaft connects to all the links and it was almost falling out. I'll have to do something about that, although it didn't seem to be slipping when pushing on the gas pedal.

I re-bled the fuel system again, and routed the return into a seperate tank instead of looping it.

Started up pretty well at this point. Got it to idle pretty well at 750 rpm. Then, to my surprise, I got it to rev up to 4000 a few times. Response was slow, but the engine sounded pretty good. I shut it off and re-looped the return. started right up again and idled strong.

Drove it around the block a couple times then, it was a total dog till around 2,500 rpm then it was just slow. I couldn't always get it to even rev this far. Shifts were really rough too. Felt like progress though, I hadn't driven the car for over six months at this point.

My question now is how big of a performance loss is the leaky injector? Could it possible be the only problem now or is that pretty unlikely?

I plan on swapping it with one of the working ones from the old engine when I retrieve it from the shop anyway, but I'd like to hope that this is the problem at this point. . .

I'm leaning towards an air issue. can you see bubbles in the inline filter? a small one is normal, but you should not see bubbles moving thru the system. or try adding a clear hose on the return. that will tell you what is coming out the IP.

__________________
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 IP has a clear return return line and I didn't see any bubbles. . .

I intend to loop the return back to the diesel tank, but I need to drill a hole in it first. It's a little stainless steel job the students had made that sits in the side of the trunk and despite my strong opinion otherwise they didn't plumb it for a return line.

The engine didn't run any differently with the return going to separate tank then it did when it was looped, I tried it both ways.

I have a new black primer pump. I will install that next and swap the leaky injector and see if things improve.

Thanks for the responses everyone!

I adjusted all the linkages according to the shop manual and it made a minor improvement. Then I adjusted the alda fully ccw and noticed a major improvement. Completely removed the ALDA and it ran like it is supposed to. I replaced the leaking injector too and now I have a running car again!

Only problem would be the fuel squirting out of the injection line fitting on top of the IP. Gonna have to do something about that. . .