66 Underhood Wiring Harness

[Rascal M]

My 66 mustang coupe orginally came from factory with a 6 cylinder and i've upgraded it to a 351 windsor. Question is, will the wiring harness from the 6 cylinder work with the 351? I can't get the solenoid to kick in when I turn the ignition switch to start. I can cross over the solenoid with a screwdriver and it will crank the engine. I have the wiring diagram but unable to figue it out.

TIA
Glenn.

 

[Tim65GT]

As long as it is in decent shape, yes.

As far as your start problem...

Is it a C4 trans? If so, there is a park/neutral safety switch in the circuit.

There's a red/blue wire that originates at the ign switch and goes through the firewall connector to another two wire connector near the accelerator linkage on the firewall that goes down to the transmission.

Check there to see if the crank voltage from the ignition switch is getting that far. You can also temporarily bypass the neutral switch by shorting the two wires together to see if this is the problem.

 

[Rascal M]

Thanks Tim, I will check it out. But my mustang came from factory with a 3 speed manual trans so I don't think it has the neutral safety switch, but not sure.

 

[Rascal M]

Thanks Tim, you were correct in that the problem was with the Neutral Safety Switch. I don't know if the wiring harness had been changed in my car or if that was the way it was from factory. Oh well it doesn't matter now that I was able to get the 351W fired up over the weekend.

Again thanks for you help.

 

[Tim65GT]

Your welcome.