D4 Starting Problem could use some prof. help

Black smoke and won't take off on it's own? The first thing that comes to mind is possibly something blocking the air intake somewhere, like maybe a rag stuffed in somewhere that got overlooked?

Don't laugh. .there was some discussion about someone who shall remain unnamed (t'weren't me:lol😊 that did something like that some time ago.

Happens over and over!

I got a parts engine with a pretty substantial rag in the intake runner to #1 cylinder. I wonder if that's why it was for sale😆

Digdeep,

One other place to check is the injection pump and linkage to make sure the rack is getting full movement at the pumps and it isn't sticking. I bought a D4 a few years ago that "was running when parked", when I went to fire it up it would puff some black smoke but wouldn't take off. When I disengaged the pony clutch it would rumble a few times and die. After checking it over, I found that the rack wouldn't move but a little. Freeing that up took care of the problem.

Also, if you had the front of the engine apart, could there be a possibility that the gears are out of time with each other, particularly the gear that drives the injector pump? If you didn't get that deep into it, then you can disregard this part.

Just a couple more thoughts. . .

the other posibility is the pony pinon isnt throwing out so its holding back the main engine try disingageing the pony clutch when you get the black smoke....👍

how did you make out with the starting of the d4 ?

Thanks for the input guys, I was busy the last couple weekends and just now got back around to this mission I aim to conquer. I checked for blockage in the air intake, All clear,oil at proper level (not too high). I also tried disenguaging the pony motor after a puff of black smoke. rule But she did not take off on her own. Also can rule out timing as the engine was not taken apart. I did notice however that when cranking the pony motor with the main motor clutch and main motor turning the oil pressure went up as it should but the fuel guage stayed the some showing no pressure. I vented the lower and upper fuel vents and closed when no bubbles present any more and also vented just above the injector pump on all 4 injectors (one at a time) fuel squirted as it should. Then I removed the fuel pressure guage to test it (mabe I'm still air bound somewhere???) Of corse I don't have the proper fitting to hook up to my air compressor and i'm not sure what the proper pressure should be. Just for kicks I started the pony again cranked the main motor and held my thumb over the open fuel line where it was attached to the pressure guage and I barley felt any pressure and could easly hold back the fuel with barley any pressure with my thumb. Is this as it should be?? or should I have more pressure here?? My manual does not mention this. I looked at the fuel filters an they look fine,fuel seems to be able to pass through fine. Does the pressure into the injectors need to be high in order for them to work properly?? I will test the guage to see how much pressure it takes to reack the green area or if it works at all?? In the meantime I will check the pump rack to see itf anything is stuck as suggested and try bleeding the lines again ,not sure if air bound would cause this problem. Again thanks and I appreciate any help or ideas. I'll get this old girl running yet!!!!!!!!!

As long as there is no fuel pressure
As long as the fuel pressure gage did not move
You can not start the engine
There's smoke but no starting

Overflow pipe
It comes out on the right of the fuel filter
It has a spring valve
Check the valve is not stuck in an open position
Check fuel supply in Engine connection point

itzik

Jusy curious, if the valve were stuck in the oper position would'nt fuel be comming out of the tube?? I did check for fuel and did not see any comming out when cranking. I also checked the injection pump and all plungers are moving.