Dash light switch & under dash harness question
 

Hey Guys, rewiring a '35 just finishing up putting in a new under-dash wiring harness( first timer at it on vintage Ford) Came across two issues:

1- I have three wires left to tie in, yellow, Black & yellow and Black & green, all for the fuel gauge per the schematic / diagram. However the original harness does not have these and the gauge has no connection points for them? Instead a bare 3/32 " solid copper conductor / wire which is connected to some type of sensor on the gauge and the other end of the conductor goes all the way to the rear along the drivers side of the frame. Anyone know what the deal is?

2- The Blk-Blue wire going the the light switch on the dash ( removed switch to front of dash to work it ) the blk-blue bullet lug fits very loose the other connections which go to the dash lights is secured / snapped in OK on that bullet lug. I have been told to solder the light switch to the wire at the bullet connection. Seems like I Probably should get a new switch before soldering?

Re: Dash light switch & under dash harness question
 

1. 35 Ford does not have an electric fuel gauge. Your gauge is hydrostatic operating on air pressure developed by the gas tank sending unit. The air pressure is transferred to the back of the dash gauge by a small tube (original is steel tube replacement is copper). Your harness is for a 36 Ford, that does have an electric gauge. That is why you have the wires.
2. The dash light switch is a rare bird. 36 is slightly different than 35. both connectors on the switch take the same connector terminal. It appears like the bullet but is blunt and stubby. The 35 switch has a small spring loaded ball bearing that retains the terminal. a small amount of oil on the spring and working the ball will free it up, no need to solder. If the two terminals on the back of the switch are distorted and nearly touching each other place a small piece of rigid plastic between the terminals that slightly forces the two terminals back straight. The switch may start to work again.

Re: Dash light switch & under dash harness question
 

The fuel gauge on '35 Ford is hydrostatic not electric. '36 was electric. Your wiring harness may have been made to cover both '35 & '36 so for '35 the gas gauge wires would not be used. Some of those wires could be for the dash lights.

Re: Dash light switch & under dash harness question
 

Thx Terry, I kept the section of old harness in the garage and when compared they are the same type bullet. I do see the ball bearing / spring. the one for the harness bullet is rusty, will work on it to see if it frees up. If not a new light switch isn't a bad thing.
thx again for the help.

Re: Dash light switch & under dash harness question
 

Thx John, in my heart I knew it couldn't be easy. Will try to enjoy exploring.

Re: Dash light switch & under dash harness question
 

Terry, also thx on on shedding light on the fuel gauge as well.