Need Help with a Model A that’s Overcharging.

[crazycasey]

Stumped you guys too, huh?

[nkaminar]

I recently came back home after being away for more than two weeks. I tried to start my Model A yesterday and it would not start. I checked the spark and cleaned the points. I got a good spark but it still would not start. I was turning to the fuel system when I remembered that I turned off the gas and ran the carburetor dry when I left for my trip. I turned the gas on and the car fired right up. I went to town after I stopped banging my head against the wall.

[crazycasey]

Originally Posted by nkaminar

I turned gas on and the car fired right up.

Riding motorcycles since my early 20’s, the petcock becomes the first thing you check.

[Badpuppy]

Fouled plugs? Shot in the dark, but it sounds oddly familiar to me, many years ago.

[Big hammer]

What you did by pulling the spark plug straps was creating a spark intensifier. The gap between the rotor tip and the distributor body points creates this spark intensifier. I would clean and gap the plugs or replace them, clean the rotor tip and the points in the distributor cap. Run with the plug straps gapped as you have after awhile should clear the fouled plugs.

[crazycasey]

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Originally Posted by Big hammer

Run with the plug straps gapped as you have after awhile should clear the fouled plugs.

So, I ran it with the leads disconnected for maybe 15 minutes at a fast idle, about 1,200 rpm, and it ran great the whole time. So I reconnected the leads, and it did fire up again (with a little more effort than with the leads disconnected). After about a minute it started missing, cutting out a cylinder here and there, and after maybe three more minutes it died completely and didn’t want to start again.

I’m going to throw another set of plugs in it (these only have 15 miles or so on them), but I’m assuming that something is causing the plugs to foul. I’m leaning towards a weak coil. It ohms fine, but the points look fine, and I know the power wire is delivering adequate voltage. A coil is cheap, and will eliminate a variable. Thanks for the info!

[rotorwrench]

It may be the condenser too. Coils can have a crack in a winding that allows it to make contact and function until it warms up and then the crack opens far enough to kill it. A non functional condenser will severely weaken the high tension voltage or kill it all together depending on how much capacity it's losing.

An excessively rich condition can wash oil off the cylinders and cause spark plug fouling. Worn or damaged piston rings can as well. It takes a fair amount of oil to foul the plugs. Black exhaust smoke is too rich. Blue exhaust smoke is too much oil.

[Elmopquackenbush]

I have some CRAZY ideas as to your overcharging problem.
1. The "Box" on top of your Generator is definitely not a Ford Cut-out and perhaps it is not functioning as intended, thus failing to interrupt the output of the Generator as a Ford Cut-out would, causing the overcharging problem.
2. Is it possible that the two wires connected to the mysterious "Box" have been accidently reversed and connected to the wrong terminals?
3. Is the frayed wire on your Generator, shown in the attached picture, shorting to the Generator housing?
4. Would adding a third wire grounding the Generator housing to the frame of the vehicle help?
5. Is the bottom surface of the Distributor corroded and thus preventing a good connection to ground?
6. This is the CRAZYIEST idea of all - your video posted above shows the sparks jumping the air gap you set up........could that possibly indicate that incorrect wiring has caused a reversed polarity i.e. Negative Ground situation?

[Elmopquackenbush]

I have some CRAZY ideas as to your overcharging problem.
1. The "Box" on top of your Generator is definitely not a Ford Cut-out and perhaps it is not functioning as intended, thus failing to interrupt the output of the Generator as a Ford Cut-out would, causing the overcharging problem.
2. Is it possible that the two wires connected to the mysterious "Box" have been accidently reversed and connected to the wrong terminals?
3. Is the frayed wire on your Generator, shown in the attached picture, shorting to the Generator housing?
4. Would adding a third wire grounding the Generator housing to the frame of the vehicle help?
5. Is the bottom surface of the Distributor corroded and thus preventing a good connection to ground?
6. This is the CRAZYIEST idea of all - your video posted above shows the sparks jumping the air gap you set up........could that possibly indicate that incorrect wiring has caused a reversed polarity i.e. Negative Ground situation?

[Elmopquackenbush]

ooops

Forgot to upload picture...........
FRAYED WIRE.jpg