3cyl Diesel Not 'Warming Up'

[TugBarge]

Hmmmm,,,,, wonder what this little widget does? Assuming it goes in the bottom of the tank? No electricals? Maybe detects vacuum and stops fuel flow when the engine isn't running? So it's failure caused the injector pump to flood and pour fuel into the the engine block? Trying to brainstorm this....

It's cam driven, and as far as I can tell, just moves fuel to the injection pump. There's a little diaphragm seal that failed and allowed fuel to enter the case.

I walked over to my neighbors and swapped the filter, and checked tube flow (it was OK). Definitely runs a bit better but still blowing heavy exhaust and not clearing up.

 

[K5lwq]

I am wondering if any of the bits from the diaphragm managed to make it to a injector causing the issue? It almost sounds like it is not firing on one cylinder. I might would try cracking the injector lines while running to see if one does not make a difference in the running of the engine. Then pull that injector and inspect it.

 

[ovrszd]

It's just a simple mechanical lift pump. Goes on the side of the engine. One of the lobes on the camshaft pushes the plunger in/out and a combination of check valves allows the flow to the right direction.

That explains how it flooded the engine block.

 

[ovrszd]

I am wondering if any of the bits from the diaphragm managed to make it to a injector causing the issue? It almost sounds like it is not firing on one cylinder. I might would try cracking the injector lines while running to see if one does not make a difference in the running of the engine. Then pull that injector and inspect it.

And maybe allowed air into the pump which moved it to the injectors??

I don't know the bleeding procedure?

 

[K5lwq]

And maybe allowed air into the pump which moved it to the injectors??

I don't know the bleeding procedure?

Maybe so. I always just loosen the lines feeding the injectors and crank the engine until I see fuel squirting well. Then tighten the nuts back and it starts.

 

[LouNY]

It sounds to m me like at least one cylinder isn't firing. And it may be getting to much fuel or not enough air.
Have you checked the air filter?
Also is the fuel return line plugged?
Also may check the valve clearances and then injectors for spray pattern.
You can check your injectors by pulling them all out and then watching the spray pattern while cranking the engine over.

 

[TugBarge]

All great ideas. Thank you guys.

I will loosen lines and purge, and check fuel return line, air filter is OK.

I will also check injector spray and see if I can find clearance specs somewhere.

 

[Sportsman762]

I had a similar issue with a tractor running poorly. It turned out to be a problem with the fuel shut off. This tractor had a cable actuated shut off and the cable had slipped causing it to not completely open up with the cable pushed in. The engine was lugging like OP, and it had no throttle response. Once I figured out the problem I was able to re adjust the cable and it worked just fine. I would push the lever that the fuel shut off is on one direction then the other to see if that makes a difference. You might have to remove the linkage if your unable to overcome the controls. You might also try tapping very gently on the injection pump with the wood handle of a small hammer to see if something might free up if it is stuck internally.

 

[ovrszd]

I had a similar issue with a tractor running poorly. It turned out to be a problem with the fuel shut off. This tractor had a cable actuated shut off and the cable had slipped causing it to not completely open up with the cable pushed in. The engine was lugging like OP, and it had no throttle response. Once I figured out the problem I was able to re adjust the cable and it worked just fine. I would push the lever that the fuel shut off is on one direction then the other to see if that makes a difference. You might have to remove the linkage if your unable to overcome the controls. You might also try tapping very gently on the injection pump with the wood handle of a small hammer to see if something might free up if it is stuck internally.

Yep. I've saw mechanical shutoffs fail a couple times by coming loose and slipping out of adjustment.

 

[TugBarge]

My neighbor called me this morning and said he made a break through. Turns out... as he loosened the valve cover acorn nut on the 3rd cylinder (closest to the firewall) the idle smoothed out. If he retightened, the engine choked up.

I have a video I will upload later.

Does this make sense to anyone?

There is negligible blowby, air filter and intake tube is clear.

Now that that is smoothed out, it idles just fine for along time, but is not burning very clean, still unburned fuel