Ford 7740 Fuel Issues?

[Postdriver nz]

Hi.
Richard from N.Z here.
A few months ago I bought a 7740.
We use it for contract postdrving.
The problem I have is that when it is on the road under power it is very sluggish and will not rev above 1600.
Sometimes it dies completly.
It seems to be staving for fuel.
Have changed both filters.
Is there a gause type filter in the lower fuel tank.
Is there any other known issues that could be causing this problem.
Thanks in advance.
Richard.

 

[Fordfarmer]

No experience with the 40 series, but all the older ones I've owned had a fine screen on the fuel pickup. I've had a couple act as you're describing. Cleaning that screen fixed the problem.

 

[Postdriver nz]

Yea the silly thing is we used to have two 7710"s and had the same thing.
But the local tractor workshop told me the later ones don't have a tank screen.
Oh well she's in the shed now and will pull it apart tommorow.
Thanks.
Richard.

 

[RodinNS]

I forget on the 40 series systems... but I think there's going to at least be a strainer in the tank. Also check and see if it's got a water separator above the pump... What I might do is pull the line off the separator leading to the tank... or the lift pump line where it leads to the tank... and force air back through the line. Make sure to take the fuel cap off first!!! That should blow out any sludge that's in the line or strainer. I might also hook a temp line to the intake side of the lift pump and stick that in a gallon of fuel and see if the pump is actually lifting fuel. Filling the filters with clean fuel can also be helpful...

Rod

 

[Postdriver nz]

Problem sorted.
They do not have a tank strainer.
Turns out that the earth wire on the fuel pump had broken at the joiner so it was barely getting any fuel.
Thanks for you replys.
She's back out driving post again!