Starter mystery

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Dan Epperly
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Starter mystery

#1 Post by Dan Epperly »

Hate to start yet another thread, but this one has me stumped.
Car is a 63 B Coupe, 6 volt.
My starter will not work from the ignition. The solenoid will click but that's it. It will turn the engine over if I use a screw driver to jump it underneath or if I run a short 14 gauge wire from the solenoid spade terminal to the hot terminal on the Voltage regulator.
If I run a 12 gauge wire from the solenoid to the ignition switch it just clicks, same if I run the wire to the battery positive terminal!
I have a new Optima battery and I had the starter rebuilt with a new solenoid.
Why would the starter work if I run a wire from the solenoid to the hot lead on the regulator but not to the battery?
The only thing I have not done is replace the damn starter bushing. I have the tool to pull it and a relictent 18 year old son who will do it (with some financial urging) But why would the bushing prevent the starter engaging in one case yet not another?

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David Jones
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Re: Starter mystery

#2 Post by David Jones »

High resistance in the switch Dan. Take the 6 volt + supply red wire #30 off the switch and the black one #50 that goes to the solenoid and touch them together. Starter should run. If it does not then check further upstream at the light switch for bad connections.
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Dan Epperly
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Re: Starter mystery

#3 Post by Dan Epperly »

David Jones wrote:High resistance in the switch Dan. Take the 6 volt + supply red wire #30 off the switch and the black one #50 that goes to the solenoid and touch them together. Starter should run. If it does not then check further upstream at the light switch for bad connections.

Hi David.
I tried that trick and it just clicks. I even ran a long 12 gauge lead direct to the battery positive terminal to the solenoid and it just clicks. The only way I can get it to kick over is running a lead to the hot on the voltage regulator or using the screwdriver trick.

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Jay Wiener
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Re: Starter mystery

#4 Post by Jay Wiener »

did you put the starter bolt in?

Dan Epperly
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Re: Starter mystery

#5 Post by Dan Epperly »

Jay Wiener wrote:did you put the starter bolt in?

Yes. It's torqued down.
I guess what I am mostly wondering is why does it work when I jump it with a short wire going to the regulator but not a long wire to the battery?

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David Jones
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Re: Starter mystery

#6 Post by David Jones »

Dan, it still sounds like a high resistance connection somewhere. Here is a link to the 356B wiring diagram. The other end of the batt +ve on the regulator is bolted to the solenoid so is just an extension of the main batt terminal. Try connecting the long jumper to the terminal on the solenoid which is just the same electrically as connecting at the batt +ve terminal. If it does not work then you have a high resistance long wire.
http://www.pelicanparts.com/356/356B_Pa ... al_dia.jpg
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Dave Erickson
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Re: Starter mystery

#7 Post by Dave Erickson »

It sounds like it is a voltage drop issue. i.e. if it runs when your +6V is coming from the regulator or the starter primary, both of which have large gauge wire connections, but it doesn't work with a 12 ga. wire to the battery, look at all the ground connections that are part of the return path: tighten up the ground straps at the battery and at the front of the transmission. Also make sure the starter is tightly bolted in place, and make sure the paint is not preventing good electrical contact.

Dan Epperly
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Re: Starter mystery

#8 Post by Dan Epperly »

Well, an update. I charged my battery up and the starter works, so I thought my proble was the new Optima. Took it in today and they tested it and said it was good, but that it was 85 percent charged. The guy asked if I had a generator and I said yes and he said maybe the voltage reg needed adjusted? I checked the voltage at the battery cable with the car running and got a reading of 7 volts,isnt that enough? Color me confused at this point...

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Re: Starter mystery

#9 Post by Mike Horton »

Dan, check the voltage at the hot terminal of the regulator, any difference? I recently checked there on a "C" with a fresh charged Optima battery, with a digital Fluke meter, and it read just a little over 7V... with the fresh generator, the car worked well, through 3 states on his way home...
Mike

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