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Modern wiring in '40 Ford

3K views 12 replies 4 participants last post by  EOD Guy 
#1 ·
I'm starting to rewire my '40 Ford using a Ron Francis kit.
The problem at hand is that I want to use the original ignition "on-off" switch on the column drop and the push button starter instead of the Francis provided ignition switch.
I suspect I'll need to modify the power lead to the power panel by inserting a continuous use solenoid so that the tiny "on-off" switch doesn't fry. However, I can't figure out how to keep the ability to switch on lights, blow the horn, etc. without having the ignition on that the Francis panel provides.
Can someone show me a diagram of how to wire this up using the Francis panel?
 
#2 ·
relays

I would suggest that the ignition switch be only connected directly to the engine ignition. This will minimize loading on the switch. All other ignition switch loads would use relays.
The fuse block has (2) sections. (1) hot at all times and (2) ignition ON.
Other ignition switch controlled loads would use relays that are powered directly from the battery side of the fuse block.
For example the electric fan control (relay coil) would be ignition but the power (relay contacts) would be hot at all times.
The lights and horn should not go through the ignition switch but are hot at all times.

vicrod
 
#3 ·
If you could post a dia of the Francis switch it would be helpful in drawing you the modifications. But you are on the right track.... Vic is correct, the key switch controls power to the fusebox ....... switched 12v side.

Depending on how the switch is terminated you will need a couple of relays to control certain items....like the switched 12v side of the fusebox, and pwr to the coil, your starter button should get the purple wire (if Francis's kit followed GM color codes) that goes to the "S" terminal on the starter etc....

I assume your existing key switch is on/off. Would you consider puting the new key switch in and use that to control the on/off functions and still use the starter button to engage the starter, that way you wouldn't have to do any modifications.
 
#4 ·
Can we "assume" that the attached photo is the switch/lock/column drop that you intend on using? I too am of the opinion that the switch should be used only on the ignition only through a relay, keeping the Ron Francis supplied 'universal' switch as your main ignition switch and hidden from sight which is what I think you are trying to do. I'm not a real lover of those original dinky keys and steering lock switches, having in my dark past broken keys or had a couple others just wear out - but, of course, that's my opinion only:D They do look fine in the right period car (you ARE replacing that cotton covered wire to the switch, aren't you?)
 

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#5 ·
I wish I had a diagram of the Francis setup. Unfortunately, it is a "connect the brown wire to terminal 12" kind of setup and doesn't have a picture of what the completed system looks like. All I know is that there is a single 10 gauge wire hardwired from the battery to the terminal box and everything branches off from there.
The terminal box has separate fuses for:
brake/hazard,
rad fan,
air/heat,
wiper,
running lights,
spare battery,
turn signals,
acc A,
horn,
int lights clock,
fuel pump,
radio gauges,
then there are four circuits that can be either "hot" or ignition depending upon how the fuse is inserted. These are labeled:
acc B,
acc H,
acc, J,
power windows.

The column drop is as Ireland's child pictured.

My intention was to retain the nostalgic look and feel of the old key and switch. If I were to use the modern ignition switch, hiding it behind/under the dash. I don't want to cut up the dash to install it so an auxillary panel beneath may be the alternative for a location.

This isn't a show car. It is intended to be a reliable driver thus the purpose for the rewire. What was there when the car was purchased was an electrical fire looking for a place to happen.

Any and all thoughts/suggestions are greatly appreciated. Thanks all.
dw
 
#10 ·
EODGuy
Dug out the wiring package with the ignition switch and here is the best info I have.
The back of the ignition switch looks like the picture you posted and has the same four terminals.
Battery feed = Red wire goes to battery terminal on starter solenoid.
Ignition feed = Orange wire goes to terminal #1 on the panel
Accessory feed = Brown wire goes to terminal #2 on the panel
Starter (center terminal) Lt Blue goes to terminal #4 on the panel. This wire is hot only when the key is in the engine crank position.
The original equipment ignition switch on the column drop only has 3 terminals for:
battery
gauge
coil
 
#11 ·
Cool...... now What does terminal #1, #2, #3 and #4 go to / do.......

#1 (Org) goes to a relay? to a wire that feeds the coil? etc...
#2 (Brn) goes the the buss bar in the fuse block that's hot in accy and run (using a multimeter to verify)
#3 ????
#4 (Lt Blu) goes to relay? straight feed to starter wire etc.....

This would be easy if I had this in front of me lol....
 
#12 ·
I've about run out of ideas/info. The Francis panel is sealed and I can't determine where each terminal goes after it ducks under the cover.
I think the best approach at this time is to abandon the original ignition switch in place and use the RF switch in an inconspicuous location. Just wire the car per the provided instructions and forgo the nostalgia. Reliability will trump again. Dang.
Thanks for the help. Really appreciate your efforts. Sorry we couldn't crack this nut.
dw
 
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