Ford ignition resistor

[Bruce Parker (RIP)]

I learned something new today, or at least noticed if tor the first time. I'm tuning up the carrier and replaced the ignition resistor in the dash. The carrier is running all the original spark parts and has the early 'diver's helmet' distributor, 6V positive ground.

Checking the voltage across the resistor it went from 6V in to maybe 1.5V out. But wait, aren't these supposed to step down from 6 to 4 volts? I hooked everything back up and so far it's starting on the first push of the starter button every time (I know Rob, shocking for a Ford, but at least no oily mess to mop up). There was a distinct new burning smell which dissipated quickly and, on checking the voltage across the resistor while running (I won't lie, it had me worried) it read a healthy 4 volts.

So do these things need to break in? Do they need to warm up? The resistor is not WW2 NOS. It's one of those Mac's Auto new ones that needs a little filling to fit the original bracket.

[David Dunlop]

Hi Bruce.

What you have noticed, might be a function of the type of meter you used to test the resister.

David

[rob love]

Originally Posted by Bruce Parker

(I know Rob, shocking for a Ford, but at least no oily mess to mop up).

In my experience, anything mechanical will eventually wear. In the case of a Ford, leave it be for the night and it will heal itself.

[Lynn Eades]

Bruce, How they work: Turn on the key and immediately you have 6 volts. Hit the starter and you get 6 volts to the nominally 4.5 volt coil. (less whatever cranking load does?) Anyhow that gets you started with good voltage. With a Chev driver, two minutes in, with the key on and the michrome? wire is red hot( thats why its in a cage, to stop him/ she, it, +etc. burning (gender neutral self) and it is down to 4.5 volts. Now try and start it and the cranking load drops (further) the voltage to the coil to 3.5 volts (my example) and the bloody thing wont start. Now the Chev fan hops out and mumbles under his breath about bloody Fords. The actual fault is him and his lack of knowledge / procedure.
I would think your new unit had some preservative / contaminant on it. You have cleaned it. Now just wait for (quoting Rob) it to heal its self.

[Hanno Spoelstra]

Originally Posted by Lynn Eades

Bruce, How they work: Turn on the key and immediately you have 6 volts. Hit the starter and you get 6 volts to the nominally 4.5 volt coil. (less whatever cranking load does?) Anyhow that gets you started with good voltage.

I have bypassed the ignition resistor and use a 6V Bosch coil on my F15A.

[rob love]

A method of cheating would be to run a wire with a diode to prevent feedback from the starter motor (or the solenoid) to the coil. It would give you full cranking voltage (engine hot or cold). Just remember which way to place the diode if you are running positive or negative ground.

This would also work for the poor chevs as well, although you will want to use a good insulated wire to resist the rot of all the leaking oil.

[Bruce Parker (RIP)]

Originally Posted by rob love

although you will want to use a good insulated wire to resist the rot of all the leaking oil.

Oil is a preservative which explains why Chevs looks so good for so long.

[Bruce Parker (RIP)]

Well I'm floored. My carrier (a Ford) has started with one push of the button for almost a week now. Even after sitting overnight...like for a full 24 hours!! It's never been that agreeable. And yes...sure...I just did a battery to spark plug refresh with new parts, cleaned connections, the works. I've gone that route before but it always retained some hesitancy starting I could never quite pin down, unless because of some undefined vehicular 'spirit' (which I truly believe in).

Now, I can't argue with results. But note that a Chev can sit in a field for twenty years and start with a semi-charged battery and a squirt of gas. It will run with any conceivable combination of worn out parts and loose connections. A Ford, after that much time, would require 2 gallons of diesel thrown down the pipe, time to absorb it, and still remain seized solid.

Go figure.

I got LOTS of drip pans.