!935 Phaeton Temporary Dead Short +

[jfcrash]

1935 Electrical System temporary shorting –

Back ground-
Car is a three year old restoration with a new wiring harness including resistor, fuse block, ignition switch, rebuilt 3 brush generator and distributor, 6 Volt Pos ground (with a shut-off switch wired in). The generators third brush setting has been approx –4 at idle and approx + 5 amps when driving… don’t drive at night and have not had an issue till now. Have a 6V Optima battery and use a battery tender from time to time.

Day One-
Anticipating some night driving I decided to get familiar with sliding the 3rd brush on the generator and checking the results, I was driving without the generator strap in place covering the brushes. After driving and stopping several of times to adjust the 3rd brush and take notes, it seemed to me the generators body was very hot… just an observation as I have never done this before.

Day Two-
While waiting for the car to warm up in the garage, I was checking the head lights…. turned the light switch on the steering wheel one click to the right to check the parking lights, then one click to the left for low beams…then when I went one more click to the left…immediately the engine dyed and lost power to all lights and no activity on the ammeter, not even reflecting a discharge.

I could not activate the starter; the only thing with power was the horn. The fuse on the fire wall was ok, the shielded resistor on the firewall did not seem to hot and I still had 6.22V across the battery, just for a moment I noticed a slight movement of the ammeter going negative then slightly positive and then to zero where it stayed. After about 30 minutes the car starts right up, which has been consistent each time I have tried this scenario… have tried this 4 or 5 times with the same results.

I assume I am creating a short when turning the light switch... a problem I will have to find…. but what is acting as a circuit breaker till it cools off, why not blow the fuse or see a current draw on the ammeter?

Would appreciate your thoughts / experiences / guidance


Jim

[40cpe]

It sounds like a connection is tight enough to run the things you turn on up to the time you turn on the headlights. First check that all your ground connections are tight and clean, as in no paint under the connections. If the problem persists check along the wire that feeds into the car from the battery/solenoid for loose connections. The next time it shuts down feel along all the cables and wires for hot spots at connection points.

[JSeery]

If it is wired correctly and the fuse is correct it would blow if there was a short in the headlights. I would remove the fuse and see where you have power. See what happens when you turn the headlight on.

[drolston]

On the 35 battery power goes to the starter switch, with the hot side also connected to the horn as well as the wire to the ammeter. That floor mounted starter switch is the only place that one bad connection could shut off all power except the horn. Check those connections.

[jfcrash]

Thanks to each of you... I plan on visually inspecting the wiring from one end to other hoping something shows up... those two days were extremely hot and muggy... don't know if temperature or over heating of some component played a hand in the problem...

thnx,Jim

[Capt Kirk]

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When you say 3 year old restoration....does that mean that the car was working fine for 3 years and then this problem showed up? A 3 year old harness can certainly get a short but has the headlight switch been replaced or restored 3 years ago as well? I hate electrical problems but your best friend is an electrical diagram of your particular car and then switching things to see what causes the problem then looking at the diagram.

[drolston]

My first V8 Ford was a '35 coupe, but I did not remember that starter switch wiring junction from 60 years ago. I Googled "1935 Ford Wiring Diagram."

[JSeery]

Very unlikely it's a short, first it would blow the fuse. If that didn't happen it would start burning wiring. And shorts don't reset when they cool down. Something else is going on.

[jfcrash]

Yes, 100% of all wiring and a complete wiring harness and light switch at base of steering column was replaced.
I have yet to start a visual examine of the wiring.. Have thought of turning on the ignition without starting the engine and start rotating the light switch from low to high beams and see if I trip any thing again.... just collecting your thoughts right now.

Thank you, Jim

[koates]

Check the big terminals on the starter switch, undo the nuts and make sure they have not overheated. Your battery cut out switch, check for the same as the starter switch or remove it and try the system. These switches vary in quality a great deal and cause problems. Check your ammeter terminals. Are they tight, not overheated. You are looking for a problem in the power distribution part of your wiring. Also earth cables are very important. Regards, Kevin.

[Kurt in NJ]

clean the battery terminals----it's also possible the battery has a internal connection problem, try the voltmetter first on battery post(center), then on terminals, then at starter switch and other ground ----then move on till loss is found, each time trying starter switch, then lights, a bad connection with no load can read good volts, but the volts go away with load

[JSeery]

Originally Posted by jfcrash

Have thought of turning on the ignition without starting the engine and start rotating the light switch from low to high beams and see if I trip any thing again.

Be careful with testing with the ignition switch on, you can damage the coil and/or points very quickly. There is really no reason I can think of to have the ignition switch on without the engine running, your problem shouldn't have anything to do with the ignition circuit. Likewise it is not likely there are any problems in the wiring itself, much more likely a connection problem somewhere. Like the other post, start by checking your connections. As Koates pointed out, you have components in your power circuit (cut out switches) that are know problem areas. Might try removing them and see what happens (just bolt the wire ends together). Adding a bit of grease to each connection might help considerably. Also, as has already been stated, the grounds have to be clean and tight. You are not dealing with a short, you are having a problem when there is higher current demand (headlights) and the system not being able to supply it and probably overheating somewhere to create a temporary current blockage. Most likely somewhere around the battery and the starter switch.

[jfcrash]

Spent some time today making some baseline observations and have yet to examine the wiring diagram to see if the observations make sense

With the fuse removed and the ignition switch in the OFF position-
the horn worked but the head lights, brake lights, and starter did not activate and the ammeter was Not showing a discharge….

With the fuse still removed and the ignition switch in the ON position-
the horn worked but the head lights, brake lights, and starter did not activate but the ammeter was showing a discharge.

With the fuse back in the holder and the ignition switch in the OFF position-
the horn ,head lights, brake lights, and starter were active and the ammeter was Not showing a discharge….

With the fuse still in place and the ignition switch in the ON position-
the horn ,head lights, brake lights, and starter were active and the ammeter Was showing a discharge….

I spent some time under the car examining the wire harness from the front of the car to the rear. No interference with brake or clutch pedal movement, battery cables secure at the battery, starter switch and at my disconnect switch.

Checked all connectors feeding the head lights and horn….. but when tugging at the two wires leading to the right rear tail light harness, the green wire, which I was tugging on, pulled out of brass male nipple which stayed inside rubber connector sleeve…wasn’t shorted just a bad connection ?

I am going to be tied up till the middle of next week and will solder a new male end to may wire.

Does anything jump out at you folks so far.??

Thank you,Jim

[jfcrash]

The part that confuses me in my previous post is why with the fuse removed and the ignition switch on.. why is there a current draw ?

Jim

[JSeery]

Seems like your checking a lot of things that wouldn't be related to the problem you ask help on. Not sure how to help you if you don't want to except advice. Looks like your still looking for a short somewhere, it's not a short. So why go pulling on wires (and pulling connectors apart)? Why keep messing with the ignition circuits? I sure don't understand what your attempting to accomplish with all this. You stated in your OP that when highbeams were selected (high current draw) that the system opened up until it cooled down. You need to concentrate on what the high current draw is opening up, and that's not a wire!

Removing the fuse does show you that it appears to be wired up correctly. The problem should be in the:

Battery connects including the ground.
The Starter Switch and/or Connections.

[JSeery]

Originally Posted by jfcrash

The part that confuses me in my previous post is why with the fuse removed and the ignition switch on.. why is there a current draw ?

Jim

Dead short though the points, that's why you were cautioned not to do that. Which you did anyway! If you keep it up you will be replacing the coil and points.

[JSeery]

See if this helps any:

[jfcrash]

JS..... I guess I did not report it in my post that I did in fact made sure the connections to the battery posts, battery shut off switch and connections to the starter switch were tight ... I did not however undo their nuts to look for overheating.. not sure I would recognize overheating useless they might be decolored? I do recognize the benefit of undoing connections /cleaning and reattaching.

I re read the posts from Koats, Kurt and yourself and will pay attention to these areas suggested.
Thank you,Jim

[JSeery]

Originally Posted by jfcrash

I do recognize the benefit of undoing connections /cleaning and reattaching.

Need to disconnect the battery ground and make sure it has clean metal under it and then reassemble it with something like dielectric grease. Make sure the battery terminal is clean. Move on to the power side and do the same thing. Also, remove the cut out switch, they are know to be a problem area. With everything cleaned and greased up to the starter switch connection see if it still has the problem.

As a side note, Koates and Kurt are smart guys!! Always good advice.

[VeryTangled]

Originally Posted by jfcrash

...not sure I would recognize overheating useless they might be decolored? Jim

Agree with what you say about detecting heat effects. One of those laser heat-guns can do the hot-spot finding for you if the heat is actually going on at the time. Someone suggested that recently, I am just repeating it.