bypassing the resister

[coolcoupe]

I had this info somewhere but can not find in my search. I looking to bypass the resister so the coil gets 6v only when starting. Any help.

[Seth Swoboda]

Pretty straight forward. Get yourself a jumper wire with some alligator clips and jump around it. Get's you going in an emergency situation.

[Black46]

Do you have a 6 volt battery I assume. Yes you can make it permanent . So if you have a starter solenoid that has the 2 smaller posts on it..take a wire from the right side post and you can run a jump wire from it to the other side of the ballast resister (bypassing it) The small post on the starter solenoid only gets power when you turn the key so it will send full 6 volts to your points/ condenser for easier starting..and when you let off the start button your car will run on the voltage that your ballast resister allow. (lower than 6v). You can also do this same jump wire on a 12v car too to help starting. The starter draws quote a bit of current so that voltage drop can make for harder starting...so the jump wire is an excellent idea. My 46 did not have one and the old owner always had trouble starting. I did that the first week I owned it and starts almost instantly now. Hope that helps.

[cas3]

You want a solenoid that has 4 terminals on it. 2 big battery connections, and 2 small ones, S and I. S terminal is the starter button, and trigger to connect everything, and I is a direct line for ignition coil, full voltage, that then turns off when you stop using the starter and ignition resumes power thru the resisted circuit.

[petehoovie]

This is what you want...

[coolcoupe]

Sponsored Links (Register now to hide all advertisements)

Thanks again guy's. Love this site !!

[Ken/Alabama]

If it doesn’t crank with the resistor in place I’d say there’s probably a high resistance in the starter circuit causing excessive current draw and robbing the ignition circuit.

[Seth Swoboda]

Originally Posted by Ken/Alabama

If it doesn’t crank with the resistor in place I’d say there’s probably a high resistance in the starter circuit causing excessive current draw and robbing the ignition circuit.

Correct. There is trouble elsewhere. By no means should bypassing the resistor be a permanent fix. The resistor by-pass should be used only to get you going in a pinch.

You need to figure out what your trouble is and make repairs.

[ford38v8]

Originally Posted by petehoovie

This is what you want...

Pete, Thanks for re-posting this valuable information. If I'm not mistaken, this diagram and text was first submitted to this website by our own Bob Shellady, AKA supereal here. We haven't seen much of Bob lately, hope he's OK!

[koates]

If you are going to use the above diode by--pass then just any old diode will not do the job. The diode should be rated to handle up to at least 6 amps current otherwise it might burn out and stop working. Regards, Kevin.

[Kube]

Originally Posted by ford38v8

Pete, Thanks for re-posting this valuable information. If I'm not mistaken, this diagram and text was first submitted to this website by our own Bob Shellady, AKA supereal here. We haven't seen much of Bob lately, hope he's OK!

Alan, you are correct of course. It was Bob that figured this out. He sure is a great guy!
I have hidden this setup in a number of restorations. Not "needed" but makes it fun to have the engine start nearly immediately.

[cas3]

When one wires it up with the diode, you have the potential that the diode fails, allows power in both directions, and the starter motor will get power from the coil. If you use the solenoid that is made for this job, with the extra wire controlled by the solenoid, it can't fail. Perhaps not acceptable on cars to be judged, but certainly thats what it is designed to do.

[Kurt in NJ]

The diode will allow the engine to start anytime the starter is engaged even if the ignition is off on vehicles with a separate starter button, or the button on the solenoid—- e careful if working in the engine compartment an “ just bumping it over” , it could start

[slowforty]

MR petehoovie is correct . Works Great Make sure the diode is placed properly.

[aussie merc]

you can also do this with a relay if you wire it correctly rather than a diode

[Brendan]

Originally Posted by coolcoupe

I had this info somewhere but can not find in my search. I looking to bypass the resister so the coil gets 6v only when starting. Any help.

why do you want to bypass the resister? when you first turn on the switch, the resistance is low, as the resister heats up,the resistance it gets higher. sounds like you have something wrong. loose or dirty confections

[coolcoupe]

I did redo all my connections so they were clean and tight but just does not turn over like it should. I thought I would add a diode to help it.

[koates]

Engine cranking speed or turn over speed has nothing to do with the ignition resistor. If it is cranking slowly that means there is lower voltage than normally required in your system. First load test your battery which means a heavy duty (300 plus amps) load tester to really load up the battery correctly. Not just the pissy 50 amp testers most auto shops use. If the battery passes its test you then start checking battery cables and terminal ends to make sure all connections are clean and tight. Old cable terminal ends develop bad connections where they are crimped or soldered onto the copper cable. Best to install NEW heavy cables especially if it is a 6 volt system. Of course the starter motor has to be in good working order and not worn out or half full of oil and crap. A good way to check for high resistance or bad connections at terminals is to touch them while the engine is cranking and if hot then something is wrong. Testing can be done with a voltmeter. Brendan is exactly correct in his statement about how the ignition resistor works. Most people dont know this. No good just guessing with electrics and swapping out parts in the hope of a fix. Testing and fault finding is the key. If you dont understand electrics then take your car to a good auto electrician if you can find one. Regards, Kevin.

[cas3]

Brandon is correct, thats how resistors work, and Koates is correct too on testing. If you have start problems, and all cables and connections are good as you state my guess woud be a starter motor hogging too much power. Hillbillys like me, put the starter on the floor, hook up the hot lead to a battery, step on it with your foot then scratch the ground wire to the case and watch it run.
it should immediately spin up to full RPM with such vigor that it nearly jumps out from your foot. If it wind up slow, takes a few seconds to reach RPM, you have a starter problem stealing juice from the system needed to make hot spark at the coil. Civilized folks will take it to be tested, I do it on the floor.

[ford38v8]

Originally Posted by koates

Engine cranking speed or turn over speed has nothing to do with the ignition resistor. If it is cranking slowly that means there is lower voltage than normally required in your system. First load test your battery which means a heavy duty (300 plus amps) load tester to really load up the battery correctly. Not just the pissy 50 amp testers most auto shops use. If the battery passes its test you then start checking battery cables and terminal ends to make sure all connections are clean and tight. Old cable terminal ends develop bad connections where they are crimped or soldered onto the copper cable. Best to install NEW heavy cables especially if it is a 6 volt system. Of course the starter motor has to be in good working order and not worn out or half full of oil and crap. A good way to check for high resistance or bad connections at terminals is to touch them while the engine is cranking and if hot then something is wrong. Testing can be done with a voltmeter. Brendan is exactly correct in his statement about how the ignition resistor works. Most people dont know this. No good just guessing with electrics and swapping out parts in the hope of a fix. Testing and fault finding is the key. If you dont understand electrics then take your car to a good auto electrician if you can find one. Regards, Kevin.

Regarding old cables, my '38 lost all electrics during a long road trip. The problem turned out to be the braided ground strap corroded inside the cable at the battery clamp. The cable was a correct factory lead clamp molded right onto the braid, no corrosion visible, looking perfect. A temporary fix was accomplished with a cotton cord tied on the braid and pulling it sideways to get me back on the road to replace the strap at a NAPA. Just shows to go ya that a pretty gal might decide to dump you some dark night without warning.