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What effect of 12volt batt used on electrical system

PostPosted: Wed Jan 16, 2013 9:25 pm
by neal
Greetings,

I went to buy a 1955 R110 and the guy that owns it used a 12 volt battery to try and start it which it never did. does anyone know if this will do damage to electrical system like the gauges, coil, starter, generator and regulator?

Thanks,

Neal

Re: What effect of 12volt batt used on electrical system

PostPosted: Wed Jan 16, 2013 9:50 pm
by lbesq
could very possibly do some damage, depends on if there were any "resistors" before the Gauges.

others will speak up with more authority

Re: What effect of 12volt batt used on electrical system

PostPosted: Wed Jan 16, 2013 10:52 pm
by havi
In the time I used a 12v battery to troubleshoot my '54 R100, I cooked the 6v coil. The starter can take the abuse. The generator will charge it only to an extent of 6v? I dunno, but the battery needed a jump every time I had to restart it. I burnt out all the headlights and taillights. Gauges worked, but only off and on, but I think that was due to a bad ground and the light switch being rusted. The wipers worked, but I wouldn't trust them for running long. It turned the engine over fast enough that it would start. The 6v battery I had couldn't do it. In the end, I was able to drive it 170 miles round trip to a car show.

Now in the "off-season" I plan to redo the wiring altogether, and keep it 6v. http://antiqueautobattery.com/ these guys sell a 6v and 12 v battery combo that can start the truck on 12v, and run it on 6v. My thinking is to run all the wiring as 6v, and add the necessary stuff to use this type of battery.

Re: What effect of 12volt batt used on electrical system

PostPosted: Thu Jan 17, 2013 12:00 am
by redturbo
Southland IH from Lethbridge Alberta has been an IH dealer for along time. George the owner is an Ih nut. He has IH trucks from turn of the century. He sells a 8v battery, seems to start these old trucks alot better.

Re: What effect of 12volt batt used on electrical system

PostPosted: Thu Jan 17, 2013 12:26 am
by 56-S-Fan
If the 12volt battery was only used as a jumper to try and start it, its not very likely that you did ANY damage.

If you left it connected after the motor started and was running, you then become at risk to damage the generator and voltage regulator, ignition coil and 'perhaps' some of the gauges.

The problem is it all depends! For instance, you cannot burn out a bulb if it is not on. You cannot burn out a gauge if it has crappy, i.e. old connections that have high resistance, and the voltage at the gauge is say, only 8V instead of the expected 12V.

When you are jump starting a 6V system with a 12V battery, ask yourself what is being 'exposed' to the 12V. Well, obviously the starter, and starter solenoid, ignition coil, and key switch. All of these are pretty robust and can take a 12V jump start many, many times before failure. The item that is most at risk is the 6V coil. That being said my S132 was converted to 12V at some point in its life and the 6V coil was never replaced. I changed it when I gave it a tune up and discovered it was 6V. So its also hard to predict what will fail at the higher voltage.

By the way I have done the same scenario many times on my S-120. Then I fixed the weak 6 V battery issue by installing a proper ground from the battery to the frame. Starts and runs like a modern day car, well, almost. I don't know the details of your situation, but it has been stated ad nauseum, that proper battery cables (like 0 gauge) and a propery ground are essential for a 6V battery system to perform properly.

Re: What effect of 12volt batt used on electrical system

PostPosted: Thu Jan 17, 2013 12:33 am
by BruceKoukalaka
I do agree with 12 volts can ruin 6 volt parts but if it did not start as you said there may be other problems in the ignition or fuel delivery systems.

Re: What effect of 12volt batt used on electrical system

PostPosted: Thu Jan 17, 2013 11:34 am
by bedrockjon
before I converted my old KB-1 to 12v. I probably jump started it at least 50 times in the 10 yrs. out of 25 that I had it.

always contected straight to the starter, never burned anything up.

one time we had no jumper cables so the guy pushed his bumper against mine for the ground, (once upon a time car bumpers weren't made of plastic).

we then took a length of romex house wire, held it to his positive terminal and my starter and it fired right up,

now, I'm NOT saying you will have no problems, this is what I experienced.

Re: What effect of 12volt batt used on electrical system

PostPosted: Thu Jan 17, 2013 4:56 pm
by lbesq
I may not state this correctly, however here goes. As the Starter, as I understand it, is "at the end" of a circuit, going directly to it to start the truck(spin the motor over) is not as likely to create harm in the rest of the circuits. Like I said, I know I do not explain in tech language, however, GOOD ground and Proper voltage will generally start our 6 volt vehicles, IF all other things are correct. 12 Volts "could" cause problems, if applied in the wrong area. AS has been stated, your experiences may vary.
Just my uneducated thoughts.

Lloyd

Re: What effect of 12volt batt used on electrical system

PostPosted: Thu Jan 17, 2013 8:34 pm
by neal
Thanks everyone for your input...and I guess a little more detail is needed. The truck never did start and run. The owner (not me) used the 12 volt batt to just attempt to start it by turning it over I don't know how much or how many times but i know the truck never did start and run/operate. So...it sounds like he may not have done too much damage if any at all.

Thanks a lot and let me know if you have any more experiences.

Neal

Re: What effect of 12volt batt used on electrical system

PostPosted: Thu Jan 17, 2013 8:43 pm
by lbesq
As stated by others, Starter will stand the 12 volts, spins very fast, do not over crank tho, it will burn up windings if you do. I take it that the motor does turn over. if so, do a compression test on the cyl. to see where they are at. Dry will not be as good as a wet compression. If you motor has good compression(these were not that high a compression motor) Check for spark at plugs, if spark, make sure they are clean, then pour a little fuel down the Carb and give her a whirl. If she will fire, even for a couple of seconds, she will run. Make sure to disconnect the main fuel line until you know that the tank/fuel there is clean and good.
Lloyd