# 7740 injector pump issue



## Cantrellc123 (Jun 15, 2015)

I own a 7740 Ford/New Holland tractor with a fuel issue. It's not every time but increases in frequency the closer to empty the fuel tank is. I'll shut the tractor off and whenever I restart it it'll run 3-5 seconds and shut down. 
There is a hand pump over the fuel filter that after I pump it 10-12 times it will usually start, sometimes it'll require another few pumps. No issues as long as it's running but you never know when it'll do this. I'm thinking there must be a check valve that sometimes sticks but I've no idea if I'm correct or if I am where I'd find this Check valve.

Does anybody have any ideas?


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## harry16 (Dec 8, 2011)

Howdy Cantrellc123,

Welcome to the Ford/New Holland tractor forum. 

Most likely, you have an obstruction somewhere in your fuel system. Have you changed the fuel filter lately? 

See items #40 and #41 on the attached fuel system diagram. 

See items # 13 and #14 on the Separator assembly diagram. These elements are probably screens. May need cleaning.

Does the attached Fuel System diagram represent your system?? Do you have the emissionized fuel system?? Do you have a low pressure lift pump to push fuel through the system??


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## Fedup (Feb 25, 2014)

The only check valves will be in the hand primer. This was not "one Ford's better ideas". With the 40 series and early TS series both the filter, hand primer and the water separator are mounted high on the engine with no actual fuel supply pump. The lower the fuel level in the tank the easier it is to get air into the system since the injection pump has to pull fuel from the tank through all the lines and filters with no help. This gets even more difficult with the side mounted auxiliary tank when it gets near empty. I have seen this many times, and my solution is to add an electric supply pump between the tank and the water separator so the entire system is charged with a bit of pressure. Leaks at the filters are easily spotted since they become fuel leaks not air leaks. and air in the system is pretty much eliminated.


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## Cantrellc123 (Jun 15, 2015)

Thanks for the info. I'll check all that out as it appears to be my system. 

It would seem there must be somewhere that air can enter and replace the fuel but I've not seen any fuel leaks, but then again I've not really looked for a fuel leak nor noticed any fuel leaks. 

I'll go ahead and change the filter as it's close to being due. 

Thanks again.


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