5718 fuel/engine problem

First i changed piston and liner, hole in liner but then i had a problem with starting tractor ,the rack in injector pump was stiff ,cured that problem, put a new 90ah battery on today pushed diesel button in and tractor started, but have to have accelerator open full because it keeps coming to a stop the only way it keeps going is if i'm quick enough to get to diesel button and push it in,then it will stay reved up but it will come to a stop again, if i try driving it, very weak i think it something to do with fuel, ANY IDEAS???. Its a right pain as i need tractor to feed silage, plus farm and tractor are 8km away and weather here in Ireland is cold at the moment. By the way i only changed one piston and liner could the other three be low on compession causing my problem??? OR if lift pump was very weak could that be IT

Hi

Make sure that rack is still moving properly. You can move it with a screwdriver while the tractor is running to see what happens. You may have to have the pump off and get overhauled if it's sticking.
Are you getting plenty of diesel to the injection pump ? Take the pipe off the inj pump and spin the engine over to see if the lift pump is delivering fuel at low revs.
Does it run okay on the re-built cylinder ? I was just wondering if the valve clearances are okay.

Good luck

Mike

Took plate off side of injector pump had a good look and have found that number 4 injector looks ceased, plus i was poking with screwdriver and seems to have moved number 1 injector out of line with others on the rack, i was pushing down on spring and black part above with screw in it, now a piston looking part below spring seems to come up higher than the others. Now getting back to number 4 on injector pump there looks like a valve stuck in the up position tried to stick screwdriver through middle of spring to get it moving but had no luck, should i try pulling it down with force. Thanks Mike for your help.

Hi

You may find one looks higher (No.4) because there is a camshaft under them and one could be on the top of the cam lobe. Try turning the engine over to see if it changes its position. If you've one which looks as if it has moved (No.1) out of place you probably need the pump repaired professionally. There is an excellent Motorpal pump engineer not far from me. He will do you a postal service.

Mike