No start on multifuel engine

[Nickspinelli1]

Hello, new to the forum.

I've got a deuce with a multifuel engine.

The injection pump was taken apart by someone else, and I was put to the task of putting the thing back together. It wasn't fun, every corner i turned i realized there was a missing part that i had to order... anyways, I got the thing back together and hooked up all the lines to find it didn't start. At first, i cracked the injector lines to purge out any air, and i saw a small amount of air bubbles and fuel spraying out. Still wouldn't start. Then i took the hydraulic head off again, only to find that it was all gummed up again from nasty fuel. Cleaned it up, installed a new button and clip, drained the fuel tank and filled with fresh diesel, and then reinstalled the head back onto the pump. Now the truck has no fuel coming to the injectors. It has a new lift pump, and fuel is definitely getting to the hydraulic head, but its not going anywhere past the head. I first thought this was an issue with the head, so I bought a new old stock hydraulic head, only to be met with the exact same issue. What could be wrong? The fuel shutoff moves freely, so i dont imagine thats the issue, though i could take it off again and inspect if its in the right position.

Edit: The fuel compensator was seized from nasty fuel gunk. I just cleaned that out and freed it up, but didn't get a chance to start it up again, since i'm letting the fuel filter housings soak in solvent for a few days to get rid of all the sludge in them. Could that have caused a no fuel issue?

Thanks for any advice/information. Trying to learn as much as I can about these motors.

 

[Welder1]

Hello, new to the forum.

I've got a deuce with a multifuel engine.

The injection pump was taken apart by someone else, and I was put to the task of putting the thing back together. It wasn't fun, every corner i turned i realized there was a missing part that i had to order... anyways, I got the thing back together and hooked up all the lines to find it didn't start. At first, i cracked the injector lines to purge out any air, and i saw a small amount of air bubbles and fuel spraying out. Still wouldn't start. Then i took the hydraulic head off again, only to find that it was all gummed up again from nasty fuel. Cleaned it up, installed a new button and clip, drained the fuel tank and filled with fresh diesel, and then reinstalled the head back onto the pump. Now the truck has no fuel coming to the injectors. It has a new lift pump, and fuel is definitely getting to the hydraulic head, but its not going anywhere past the head. I first thought this was an issue with the head, so I bought a new old stock hydraulic head, only to be met with the exact same issue. What could be wrong? The fuel shutoff moves freely, so i dont imagine thats the issue, though i could take it off again and inspect if its in the right position.

Edit: The fuel compensator was seized from nasty fuel gunk. I just cleaned that out and freed it up, but didn't get a chance to start it up again, since i'm letting the fuel filter housings soak in solvent for a few days to get rid of all the sludge in them. Could that have caused a no fuel issue?

Thanks for any advice/information. Trying to learn as much as I can about these motors.

Just a thought are you sure you have the hydraulic head in time? It could be out 180 degrees. With the engine on the firing stroke of #1 cylinder and the balancer timing mark on the correct mark the pump should be in time and the marked tooth on the head visible.

 

[Nickspinelli1]

Just a thought are you sure you have the hydraulic head in time? It could be out 180 degrees. With the engine on the firing stroke of #1 cylinder and the balancer timing mark on the correct mark the pump should be in time and the marked tooth on the head visible.

Yes, it is in time for sure.
I forgot to mention, when i crack the fuel lines now, i get no fuel coming out of them during/after cranking.

 

[rustystud]

How completely did you rebuild the injector pump ? Did you have it totally torn down ?

 

[Nickspinelli1]

How completely did you rebuild the injector pump ? Did you have it totally torn down ?

Well, what originally happened, from what i heard, is that the truck was stuck on full throttle, and the motor would run off when started. So the guy before me pulled the pump off and stopped there.
I don't believe he touched any internals of the pump. I took the fuel shutoff/timing cover off the pump, removed the shutoff lever and freed it up, took the hydraulic head off and replaced it, took fuel compensator off and cleaned it and freed it up (have yet to try to start it since i did this). I took off the higher psi fuel transfer pump on the front of the injection pump, and nothing seemed wrong with it (after cranking, there is decent fuel pressure in the filter housings). That is what i have done to it so far. Is there anything i could've missed so far?

 

[rustystud]

When you had the "Hydraulic Head" off, did you notice the piston and snap-ring ? Was the snap-ring in place ? Also was the keeper in place on the bottom of the hydraulic head ?
There are several things that could have gone wrong. It is extremely hard trying to diagnose the problem without seeing the pump.
You said the "booster" pump is working. Is there fuel coming to the injection pump ?
You should also check and see if any fuel is leaving the pump. If there is fuel coming and going then the problem is on the high pressure side.
Have you taken off the "center" bolt on the top of the hydraulic head and seen if the plunger moves ?

 

[Nickspinelli1]

When you had the "Hydraulic Head" off, did you notice the piston and snap-ring ? Was the snap-ring in place ? Also was the keeper in place on the bottom of the hydraulic head ?
There are several things that could have gone wrong. It is extremely hard trying to diagnose the problem without seeing the pump.
You said the "booster" pump is working. Is there fuel coming to the injection pump ?
You should also check and see if any fuel is leaving the pump. If there is fuel coming and going then the problem is on the high pressure side.
Have you taken off the "center" bolt on the top of the hydraulic head and seen if the plunger moves ?

I will check the center bolt. IF its not moving, is there an internal failure in the pump?

By keeper, do you mean button/retainer clip? Or the keeper for the plunger?

I don't remember inspecting the piston or snap ring.

 

[Floridianson]

I will check the center bolt. IF its not moving, is there an internal failure in the pump?

By keeper, do you mean button/retainer clip? Or the keeper for the plunger?

I don't remember inspecting the piston or snap ring.

Thank you! Piston or snap ring? Think he means Tappet assembly, Plunger outer spring, Plunger spring seat and spring retaining ring.

 

[rustystud]

Thank you! Piston or snap ring? Think he means Tappet assembly, Plunger outer spring, Plunger spring seat and spring retaining ring.

Yes.