1520 new motor won't start

[Reedi]

1520 new motor won\'t start

Hey everyone, been lurking for quite a while, I can't find any answers in the archives, so I registered and here I am. My problem is this:
We rebuilt the motor, with oversized pistons from new holland, everything machined to the specs in newhollands book. The tractor started and ran good for about 30 minutes. We noticed some fuel seeping around the injectors, so we took the lines off, and tightened the injectors down good. Now the tracor won't start, cranks and cranks, but no fire. Yes, I bled the lines all the way to the injectors, been there a hundred times with this motor and others. Any ideas what I should look for next? the injector pump is timed with different thicknesses of shims, and I've tried all different ones. I've gone thru the injectors, they look fine. What do I look for in the injectopr pump itself to see if it's working? Ok, i'm out of breath now /forums/images/graemlins/crazy.gif any ideas?
Thanks
Reed

 

[MikePA]

Re: 1520 new motor won\'t start

Does the 1520 have any kind of safety interlocks that would prevent starting?

 

[Reedi]

Re: 1520 new motor won\'t start

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Not to keep it from firing, just to keep it from cranking (like a clutch start safety) i also verified the fuel solenoid is opening.

 

[DavidJ]

Re: 1520 new motor won\'t start

What happens if you spray a bit of starting fluid into it?

The fact that it ran for 30 min tells me that it has something to do with the work on the injectors.

Are you sure that the injectors are opening? You can take them to a shop and have them tested.

 

[Soundguy]

Re: 1520 new motor won\'t start

Are you getting black puffs of smoke from the stack?

Soundguy

 

[Reedi]

Re: 1520 new motor won\'t start

Figured it out! The injection pump has a rod that slides back and forth, which turns a little shaft for each injector line, which has a curved notch in the end to deliver the fuel to the injector: more turn of the shaft = more of the curved notch opening to the injector line = more rpms. Opposite of this is less turn of the shaft = no fuel. Well the shaft was bound up a bit, sos I took thte pump apart, figuring what the hey, if I got to buy a new pump, might as well look inside this one. Turns out, the guts of the pump had a little tit of metal which was supposed to hold a pin from turning, which had broke off. the pice must have been binding up the back and forth shaft. Well, I fixed the tit, reassembled, bled the lines, wouldn't you know it, she fired on the 2nd cylinder I was bleedin.
Thanks for all the advice.
Reed