Fuel timing 2008 NH T2420 w/ Shibaura N844LT engine

[Craig Gleason]

I bought this tractor used and it never ran well. It was hard to start and lacked power. The hour meter was broken but I suspect it has many many hours on it. After having a New Holland dealer work on it with very limited success, I pulled the engine and just had it rebuilt. I'm now installing a brand-new fuel pump into my newly rebuilt engine. The fuel pump runs directly off the camshaft and you adjust the timing by adding or removing shims behind the pump. I'm following the spill timing procedure in the manual. I verified top dead center and ran the spill procedure several times with the same results. Here's my problem... I cannot get it to advance enough. Even with no shims, I am about 9 degrees too retarded. Does anyone have any ideas for me? Is it possible that the lobes on the camshaft are worn down that much? There is no visible evidence of that but I can't think of what else could be the issue. Any help is appreciated!

 

[thepumpguysc]

Idk if it’s written in the manual or not.. but u have to have the pump control rack in a certain position..
All the way 1 way and it’s in shut off..
All the way the other way and it’s in max fuel..
U have to set it in the middle.
Did u take out the center of the delivery valve & remove the spring and torque the holder back down..30 ftlbs..
What are u using for fuel pressure.??
What are u using for a drip tube.??
Are u sure you found TDC.?
Are u turning the engine in the correct normal rotation.??
Last one I did, there were notches in the front pulley..
1 for TDC and the other for the inj. pump..
Good luck

 

[Craig Gleason]

Thank you for the quick reply! Here are the answers to your questions...
Idk if it’s written in the manual or not.. but u have to have the pump control rack in a certain position..
All the way 1 way and it’s in shut off..
All the way the other way and it’s in max fuel..
U have to set it in the middle.
No, there is nothing in the manual about this. The rack gets connected to the governor via a thin strip of metal before you install the pump. Should I leave that disconnected while spill timing? The shut-off plunger is removed.

Did u take out the center of the delivery valve & remove the spring and torque the holder back down..30 ftlbs..
Yes

What are u using for fuel pressure.??
Just free-flowing via gravity. It requires that you fabricate a tank to bypass the lift pump which I did.

What are u using for a drip tube.??
I fabricated a gooseneck tube about 3" long. I get a steady drip which slows as I turn the engine on the compression stroke. I'm turning the engine slowly until the drip gets to 1 drip per sec. then a 1/2 degree after that, it stops completely. That's where I have been checking the timing marks.

Are u sure you found TDC.?
Yes. I used a dial gauge on the piston.

Are u turning the engine in the correct normal rotation.??
Yes

Last one I did, there were notches in the front pulley..
1 for TDC and the other for the inj. pump..
Mine has just one that I verified on the TDC mark. The correct timing is 19-20 degrees before. With no shims, I keep getting 11 degrees before.

 

[thepumpguysc]

Do what u have to do to put the rack in the middle..
Use a rubber band or a screwdriver..
The fuel coming out of the tube should be a stream..
Then as you’re turning the engine it slows to a drip..
KEEP TURNING until it slows way down but not off..
THATS WHERE port closure is..
Good luck

 

[Craig Gleason]

Roger that. I'll let you know how it goes.

 

[Craig Gleason]

Keeping the rail in the center and stopping when the drops slowed (not stopped) changed the results to 18 degrees before TDC. I'm going to try it there. Thank you for the help.

 

[rScotty]

Thanks to both Craig and "thepumpguysc" for a good discussion. I've enjoyed following along.

rScotty

 

[thepumpguysc]

Thank u for trying and posting the results.!!