Bleeding Newholland L785 New Holland

[Rgory]

I was curious if anyone had any experience with the fuel system on a New Holland L785. The machine ran when it was parked for service it had a new fuel filter put on and then wouldnt start. The injection pump was taken off and rebuilt and the manual primer was replaced. The machine still wont start, it has no fuel pump and the tank is sitting lower than the injection pump, I am at a loss as to how the fuel is supposed to get sucked up.

I am working with a qualified mechanic and we are both at a loss, we are considering adding an in-line pump to get things primed/going, however I am curious if I am overlooking something simple.

Curious if anyone might offer a suggestion or two?

[cat320]

It's funny my friend has a 185 and the thing just died on him one night we tryed everything he even called nh up . some so find out his started went bad . I would of never thought that especially since it was running when it died but ya never know i guess.

[Rgory]

Cat,

I will definetly keep that in mind, The starter was replaced within the last year or so. I am thinking that isnt it. I believe the problem may lie in our bleeding procedures. I cant see New Holland designing a system that couldnt prime itself, I must be missing something.

[Pelican]

I don't know that particular machine, but I can't say I've ever seen a machine built without a fuel pump, especially with the tank lower than the engine. What you might try doing is crack a line on the injector side of the pump and pressurize the tank with air. Be sure to use a regulator, I wouldn't go above 15 PSI. You can put a air line with no connector in the fill pipe and ball up plastic sheeting around it to make a seal. You should see fuel flow from the cracked fitting after a bit, then tighten it. See if that gets you anywhere.

[stargazer]

I don't know that particular machine, but I can't say I've ever seen a machine built without a fuel pump, especially with the tank lower than the engine. What you might try doing is crack a line on the injector side of the pump and pressurize the tank with air. Be sure to use a regulator, I wouldn't go above 15 PSI. You can put a air line with no connector in the fill pipe and ball up plastic sheeting around it to make a seal. You should see fuel flow from the cracked fitting after a bit, then tighten it. See if that gets you anywhere.

Pelican, I like reading your suggestion. Very practical and results oriented sounding. Sometimes, if air can be removed, things just work.

[98Chevy2500]

I own an older New Holland L555. I have also had the same problem with mine. These are the priming procedures for my machine, that has worked every time.

Loosen fuel filter and pump hand primer till fuel spills out and no more air bubbles. Hand pump only pressurizes to the fuel filter, if I remember correctly the injector pump takes over from there.

Tighten fuel filter and make sure their are no leaks.

Break each injector line loose, one at a time, and crank engine till all air is removed and fuel streams out. Each line takes only 10-15 serconds. This is easier to do with two people and fresh batteries.

Tighten injector lines and machine should fire right up.

Their is no automatic air bleed system on many older new hollands.

[Ron's Asphalt]

Do yourself a favor and keep a battery charger or jumper cables hooked up while doing his suggested bleeding method, which should work.

[Rgory]

Thanks guys, I appreciate everyones advice. We ran the battery down a bit yesterday so it trickle charged all night. I am off to work now so I will let you all know how it works out.

Ryan

[Rgory]

Well we got the machine going, it seems that there was something blocking fuel flow in the filter assembly even though they were brand new filters. After we cleaned that out and primed each injector the machine fired right up.

Thanks for the help and good ideas guys.

Ryan

[Arc Burn]

I know you got it but i was just thinking,i used an aftermarket filter on one of our 50 hp tractors and it came with an o-ring that was not used in my application,i put it on not really knowing/paying attention,turns out the o-ring completly blocked the flow of fuel thru the filter,just an idea if someone else searches this thread.