'54 Ranch Wagon electrical confusion: Switch?

[JimNNN]

Hi folks. I rewired my Ranch wagon more than a year ago. The job was pretty thorough and I replaced pretty much everything electrical from wires to relays to switches, including the starter switch. Generally, everything works well.



I've noticed lately, however, that my dash gen and oil light are staying on after I turn the car off and pull the key out. (????) My assumption was that it was the starter switch, even though I'd replaced it with what seemed like a quality unit from Ron Francis during the rewire. I ordered another switch, but thought I'd better check with you guys before I put it in just in case you had a more plausible or likely explanation for the problem.



The problem is intermittent, so it's kind of hard to establish cause and effect. I turned the existing starter switch to a different angle in it's mounting location thinking that a wire was shorting/making contact with another (even though I couldn't visually see that.) The problem stopped, then came back. Thanks for any help.

 

[dmsfrr]

There was a similar problem posted here recently, it may be a sticking switch contact inside the voltage regulator.

 

[JimNNN]

There was a similar problem posted here recently, it may be a sticking switch contact inside the voltage regulator.

Interesting. Thanks for the reply. I could see how that might get the gen light to go on/stay on as it connects to one of the leads in the volt. reg., but the oil light too? I should also mention, the oil and gen lights are often on at different intensities when this problem happens. And the intensity can also vary from incident to incident.

 

[dmsfrr]

Interesting. Thanks for the reply. I could see how that might get the gen light to go on/stay on as it connects to one of the leads in the volt. reg., but the oil light too? I should also mention, the oil and gen lights are often on at different intensities when this problem happens. And the intensity can also vary from incident to incident.

That's not as weird as you might think. If you have a wiring diagram this explanation is much easier to follow.
I'm looking at a '55 wiring diagram, hopefully they're similar enough.

The Gen light is connected to the Armature terminal of the voltage regulator.
If battery power is still on the Armature terminal with the key off... it's finding a path to ground by going thru the Gen bulb then to the common power connection on the ignition switch with the Oil pressure light, then thru the Oil light bulb (at reduced voltage) and grounding thru the oil pressure switch on the block.

Because of the common Gen and Oil light power connection on the ignition switch there may also be some (reduced) voltage present on the Battery side of the ignition coil, grounding thru the coil and points when the points are closed, but apparently not enough to run the engine.
The points being open or closed to an additional ground, with the added resistance of the ignition coil, could account for the different intensity of the Gen and Oil bulbs at different times.
.

 

[JimNNN]

Thanks for the explanation dmsfrr. Do you think that the voltage regulator can be fixed (by me) or should I get a new one?

 

[JimNNN]

Okay, for those folks who are listening into this conversation, I believe this is the thread that dmsfrr is referring to:


https://www.fordbarn.com/forum/showthread.php?t=286444&highlight=gen+light+stays


According to the thread some people have had success just knocking the VR lightly with a wrench when the gen light goes on. It loosens the sticky cut out switch. I think I'll try that. If it works, I may use that as standard procedure, as I've already had two substandard voltage regulators since the rewire. Are the new 6-volt voltage/generator regulators really that bad quality?


BTW, rotorwrench says in the thread that it could also be the keyed ign. switch. Once again, the switch in there now is nearly new, so I wouldn't think it would be the issue.

 

[dmsfrr]

Thanks for the explanation dmsfrr. Do you think that the voltage regulator can be fixed (by me) or should I get a new one?

You're welcome. My suggestion in the other thread was to clean the relay/switch contacts in the voltage regulator. Emory cloth, a points file or even fine sandpaper, after disconnecting a battery cable.
.