Looked at a 91 7.3 today.

[PowerbyFord]

I looked at a truck today, and found a strange item. Someone ran a jumper wire and a toggle switch to the wire on top of the fuel filter housing. When you flip it, the GP solinoid clicks. The truck runs great, but you have to have this switch on to start it, and it shuts the truck off too. Is this supplying power to the engine through this wire?

 

[punkmechanic]

Its hard telling what they did. Sounds like they have a toggle to the injection pump shut off solenoid, but that has NOTHING to do with the filter housing. the only sensor on top of the filter housing is air in fuel and that is just an idiot light on the dash.

can you get a pic of it? I could give you a better idea with an under hood pic, and a closer up one of the connection on the filter housing.

punk

 

[Black dawg]

the fuel heater,cold advance, fast idle, injection pump sol, and glow plug controller all have the same power source.

 

[Goofyexponent]

my truck is wired like that too...It's getting changed this winter!

 

[PowerbyFord]

So should the GP solinoid click like that? The wait to start light comes on for a sec then goes out. The truck only has 148000 on it, and runs great. Could they have just bypassed a fusible link maybe?

 

[Black dawg]

probably has burnt fuse link at the starter relay on the fender.