Ignition switch woes

[Will D]

For testing purposes can the ignition switch be replaced with a basic 30A toggle switch? On a '38 fordor.

Been having a heck of a time tracing an intermittent issue causing the car to die. Figured out last night no power was getting to the coil from the ignition switch, well at least not all the time. When I hooked my multimeter to the switch and wiggle it in the on position power would cut in and out...

Second question. When testing resistance on an ignition coil, what should primary and secondary readings be? The coil is 42-48 style.

[drolston]

Rebuilding the ignition switch is tricky but doable by anyone with reasonable small-motor coordination. I did it decades ago on my '35 coupe and would not want to have to do it again. To prolong the life of the ignition switch on my '41, all of the accessories (heater, wipers, radio, GPS, phone dock, turn signals, etc.) are on a separate power switch under the dash lip. The only things I have on the ignition switch are the coil and the electric fuel pump. It would be pretty easy to put those on the added switch as well, but I would want the ignition on a separate switch for those times when I want to listen to the radio with the engine off. .

[Phil Gillespie]

Originally Posted by Will D

For testing purposes can the ignition switch be replaced with a basic 30A toggle switch? On a '38 fordor.

Been having a heck of a time tracing an intermittent issue causing the car to die. Figured out last night no power was getting to the coil from the ignition switch, well at least not all the time. When I hooked my multimeter to the switch and wiggle it in the on position power would cut in and out...

Second question. When testing resistance on an ignition coil, what should primary and secondary readings be? The coil is 42-48 style.

For test purposes yes this basic toggle switch will do the job.
Guessing coil resiistance, primarly around 0.8 ohm secondary 6 to 8 kohms.
Presuming 6v system.
Phil NZ

[msstring]

I set up all accessories on a relay that is another way to reduce the load on the switch.

Sent from my SM-G973U using Tapatalk

[Ken/Alabama]

Also check resister under the dash for Dirty or loose connections.

[Will D]

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Didn't realize how simple and serviceable the stock switch is. Was thinking to install a toggle switch till parts arrived but a good cleaning was about all it needed. This issue had me banging my head for quite a bit. In the end I ended up addressing allot of other things which needed to be done but were not the main issue....so happy it's running again!




My coil reads 0.6ohms primary and 6.55ohms secondary. I have another coil which reads the exact same. It came with the car in a box of parts but not sure if maybe it's been rebuild as it has a black cap and brown lower case. The seal doesn't look new but did these coils ever come from the factory black and brown? Says "made in USA" on the top and a "C" on the bottom. I'm going to try it out and carry the known working one with just in case.

[v8fordman]

I have a Ford script '37-'41 coil that is black and brown, so at least there were a few that got mixed in their manufacturing.

[Terry,OH]

The ignition switch needs replacement and i believe your not reading the Ohms correctly should be on the K (Thousand) ohm scale for the secondary.

[Will D]

Originally Posted by Terry,OH

The ignition switch needs replacement and i believe your not reading the Ohms correctly should be on the K (Thousand) ohm scale for the secondary.

I typed it wrong. 0.6 ohms primary and 6.5 kohms secondary.

[oldford2]

Some time ago, GM (George Mitchell) posted instructions on removing and cleaning the switch, He demonstrated it to some of us when we visited him in his shop. Maybe he will re-post it.
John

[Will D]

Originally Posted by oldford2

Some time ago, GM (George Mitchell) posted instructions on removing and cleaning the switch, He demonstrated it to some of us when we visited him in his shop. Maybe he will re-post it.
John

I ended up pulling it apart and cleaning the contacts with a little wire wheel on a dremel. The outer inset edge didnt sit proper on the metal case so it was worked a little with a file. Once reassembled it fit together and works great. I'm terrible with remembering before and after photos, so no pic of cleaned up switch....