7610 Ford NewHolland rough idle

[durtfarmr]

This is a diesel farm tractor......I have replaced the fuel filters......and bled ths fule rail..........yet this tractor constantly "hunts" up and down......wether at idle or at 18oo rpm....It will drive for a short distance......then eventually stall out...Yet as soon as one "primes" the primer 3 pumps...it eventually starts back up as long as throttle is at half or better...????What could be wrong ..???/ It is an British tractor ..to the best of my knowledge

 

[KennyV]

That's a nice size tractor...
I would suspect the lift pump or a crack in the fuel line between the tank and the pump, this would give a source for air into the lift pump...
are there a lot of hours on the engine?
Remove the IP and the injectors and have them bench tested...
The "hunt" could be turbo related... but the need to pump up the prime leads me to think you are having a lift pump problem or air before the lift pump...

This is not really the correct forum for thiss tractor ... but there are a few on here with mid size, just under 100 HP tractors...
Check in at TBN... : New Holland Owning/Operating - TractorByNet.com
There should be a lot of NH guys there with a checklist for you....

Make it back to join us here at LMF.... :smile:KennyV