!935 Phaeton Temporary Dead Short +
 

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

Re: !935 Phaeton Temporary Dead Short +
 

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.

Re: !935 Phaeton Temporary Dead Short +
 

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.

Re: !935 Phaeton Temporary Dead Short +
 

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.

Re: !935 Phaeton Temporary Dead Short +
 

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

Re: !935 Phaeton Temporary Dead Short +
 

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.

Re: !935 Phaeton Temporary Dead Short +
 

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."

Re: !935 Phaeton Temporary Dead Short +
 

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.

Re: !935 Phaeton Temporary Dead Short +
 

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

Re: !935 Phaeton Temporary Dead Short +
 

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.

Re: !935 Phaeton Temporary Dead Short +
 

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

Re: !935 Phaeton Temporary Dead Short +
 

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.

Re: !935 Phaeton Temporary Dead Short +
 

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

Re: !935 Phaeton Temporary Dead Short +
 

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

Re: !935 Phaeton Temporary Dead Short +
 

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.

Re: !935 Phaeton Temporary Dead Short +
 

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.

Re: !935 Phaeton Temporary Dead Short +
 

See if this helps any:

Re: !935 Phaeton Temporary Dead Short +
 

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

Re: !935 Phaeton Temporary Dead Short +
 

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.

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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.

Re: !935 Phaeton Temporary Dead Short +
 

Why don't you remove the wire going to the coil. You should have done that if you wanted to leave the switch on. Take the light switch apart at the bottom of the steering box. You could have the high beam wire rubbing on the case going to ground.

Re: !935 Phaeton Temporary Dead Short +
 

First of all I note you may not have an original 35 Ford foot operated starter switch but instead a solenoid starter switch which is operating only with the ignition switch turned "ON" or what ? and a push button starter switch on the dash. I think by removing the fuse during testing is confusing the issue for you and us as well, so leave it in place. Leave the fuse in which should be a 20 amp or 25 if you like. I would be obtaining an original 35 Ford wiring diagram and following closely the connections on each side of that fuseholder and ignition resistor to make sure they are all the correct way around on the terminals. Follow each wire ( colour) one at a time to make sure its destination is correct according to the diagram. There is a possibility that you have a short to ground in the high beam headlight circuit and if so it should have blown the fuse if in fact the headlights are powered through the fuse. What value fuse in amps did you have fitted in there ? If you are going to have the ignition switch turned on for more than 30 seconds with the engine not running then you need to disconnect the wire at the coil to save any overheating of the resistor, coil, points etc. All the wires only connect to one place ONLY and I suggest you follow them all through carefully to establish if they are correct. A high beam short to ground could be anywhere from the inside of the headlight switch all the way to either of the headlight bulb sockets. Do not set the generator third brush any higher than about 12 amps on the dash ammeter with the engine revs up quite a bit. This is a total generator output of around 15 amps allowing for 3 amps ignition draw on the dash ammeter. Any higher will cook the generator. For normal daytime running (No lights) I only set the brush to show about 5 amps on the dash ammeter otherwise any higher will overcharge and cook your optima battery. Regards, Kevin.

Re: !935 Phaeton Temporary Dead Short +
 

Kevin, +
I do have a Ford foot operated starter switch; the fuse size is 20 amp. , and now understand the 30 second rule and I will trace the wiring as recommend..
Thanks,Jim

(but I can't help to wonder now if this whole issue of mine which took place during my two day experimenting with driving around and adjusting the 3rd brush for more current output .... that day 2 I talk about still has the generator putting out at 14+ amps while I am rotating the head lite switch... could this be overheating rather than a dead short...)

Re: !935 Phaeton Temporary Dead Short +
 

That would be my guess, a short doesn't normally reset it's self when it cools down. The problem is most likely in the battery or starter switch connection. Have you removed the cut-out switch yet?

Re: !935 Phaeton Temporary Dead Short +
 

Are you saying that with the headlights ON and engine revved up that the ammeter is showing a 14 amp charge ? With engine NOT RUNNING and headlights ON does the ammeter show a 12 amp discharge approx ? If this is the case then the generator is charging around 26 amps which is about 10 amps above its SAFE OUTPUT RATING which would be a reason its getting HOT !! When answering these questions please be very specific. Re-read my post #22 regarding setting the generator third brush. You need to get this right. Regards, Kevin.

Re: !935 Phaeton Temporary Dead Short +
 

You say that the car was running fine before you adjusted the third brush in the generator to give you more amps for night driving. It sounds to me that you have shorted out something in the generator, because, the car is starting and running until you turn the lights on. If you have a weakness in your battery and the genny is shorted out and NOT charging, then turning on the lights might just kill whatever charge is in the battery.
I would take the battery to a supplier and ask them to load test it for you. They can tell you if there is a weak cell or a problem with the battery. Then check whatever you did to the genny to make sure none of the wires are shorted and that all the brushes are contacting the armature.
Viv.

Re: !935 Phaeton Temporary Dead Short +
 

Kevin , your answer to post 25, I was driving and stopping and each time I was changing the position of the 3rd brush and taking notes of the current output at various positions of the 3rd brush for anticipated night time driving, my last mark was at 14+ amps at 30mph. I drove home from there and it stayed there(14+) till the next day when I started the car and during warn up and my rotating the head light switch did the car dye... and would not start till after a cool down. etc.
I have moved the third brush back to the original position of 4 to 5 amps where it has been for 3+years.
I have traced all wires from each side of the fuse holder and resistor to their destination per the 35 wiring diagram as suggested. Checked the wires inside the bulb at the base of the steering column and see no evidence of sparking/shorting.

I have not driven it again, but starts fine and does not short out or die when I rotate the lite switch on the steering wheel as many times as I did...

Re: !935 Phaeton Temporary Dead Short +
 

This may just be semantics to you, but what you are describing is not a short, it is an open circuit (or very high resistance circuit). Most likely caused by the generator interacting with something (most likely the battery) at the higher output levels. I would still have the battery check because it should be capable of handling the higher amperage loads. When a circuit shorts out, it is similar to fireworks with a lot of heat and burnt wiring if the fuse doesn't blow. And the fuse is another hint, it there was a short in the lighting circuit it would blow. And even a blown fuse would have no effect on the car starting and/or running as the ignition circuit is totally separate from the fuse. When everything does dead and the starter will not turn the engine over there is an open circuit somewhere in the area of the battery and the starter switch. The fact that the horn will still operate indicates that it is not a total open circuit but probably very high resistance to the point that the starter will not operate. Only thing I can relate that to is the battery if the other connections have been eliminated.

Re: !935 Phaeton Temporary Dead Short +
 

JSeery
I believe you are on to something. Test the battery with a carbon pile tester.
It may be when the battery is hot the case expands and exposes a bad connection.
Make sense?
Bruce

Re: !935 Phaeton Temporary Dead Short +
 

Listen to JSeery

Re: !935 Phaeton Temporary Dead Short +
 

I will pull the optima battery and have it carbon pile tested as suggested and install my backup nos foot operated starter switch this coming week(s) ...

If it makes sense at this time, I can also pull the generator with its generator mounted cutout and have it bench tested under load ??

Thank you for your comments, Jim

Re: !935 Phaeton Temporary Dead Short +
 

A mention of replacement of switches during restoration makes me wonder about the quality of the restoration parts. The original light and ignition switch parts as well as lamp sockets & starter switches/solenoids were all of very good quality materials back in the day. Some of the modern reproductions use inferior metals and plastics to what was OEM and can be problematic at times.

Ford started using circuit breakers to protect some stuff in later years with a few fuses for non essential stuff. The older cars don't have very good circuit protection but they are better than the model A cars that basically had no circuit protection at all.

Re: !935 Phaeton Temporary Dead Short +
 

Follow up...
Battery passed the carbon pile test...so starting with the battery terminals and undoing/cleaning/checking all connections as pictured in the sketch in post 17 above...

The problem was located at the starter side terminal of the foot operated starter switch.. the locking hardware was discolored, I assume from overheating, and covered with a white substance.
I have replaced the starter switch with a NOS switch which appears to be working fine ...
I am assuming now that the starter switch itself has had some internal problem as for some time I have had to work the foot button to find the sweet spot to get the starter engaged... causing some internal heating??

Thank you all for your help and JS for being persistent..
Jim