The Fordson Tractor Pages Forum

Hi,

My fuel shut off valve failed.
I bought a new one from QTP and installed it, it was a pain to prime the system.
When i finally got it running it was running well, i used it for some light link box duties and while she was sitting ticking over beside me, it just slowed down and stopped as if it ran out of fuel, i thought this was the case, but it was not, there was plenty of diesel in the tank.

i tried to start it up but it turns really slowly, i thought oh no it has seized! so i removed the starter motor and turned the fly wheel, thankfully very free.
So i started to try and bleed it, no joy and when i remove the fuel cap the tank seems to be under a little vacuum or pressurized
i changed the fuel filter, and when i tried to prime it up i could not get diesel into the filter bowl, so i replaced the primer pump, that filled the filter but as soon as the bowl was full the pump felt different as i pumped.
i removed all lines form tank to primer pump to filter and all clear, when i removed the line form the filter to the minimac pump there was pressure behind it, if i pump now the fuel comes out of the pump, put the pipe back and it does not want to go any further! if i release the pipe off the back of the pump there is pressure there as if the pump is blocked.
Is that possible.
Could something have happened the pump itself - how do i check this?

Thanks for any help you can offer

Sounds like two things. The vacuum in the tank suggests the breather in the fuel cap is not working, make sure you're not using an oil filler or radiator cap. Be careful with that, for if left alone it will implode the tank. As for the pressure build-up in the fuel system it's a sign of correct operation. Failure to get such pressure indicates a leak, anywhere between the lift pump inlet valve and plungers and barrels. The commonest leaks are in the lift pump. There's nowhere for the fuel to go if the engine isn't running, so it just pressurizes. As for the slow turning first make sure the battery is ok, then ensure all connections are clean and tight. If you still have slow turning check the brushes in the starter, make sure they're clean and not too short.
Sandy