The Stovebolt Site Forums The Shop Area The Electrical Bay Cooked my Batt. cable !!!

Been thinking of upgrading to 12 volts alt., (Brighter lights, electric wipers, Good tunes) Have had trouble starting my truck when it was warm. I've had to let the battery rest before she would crank with any speed at all. Sunday I skimed thru repair manual in prep to do some electrical tests. This is the time I thought I might as well "Gunk" the engine down before I get down to it.

Sunday I Gunked, an hour later I hosed everything down. Monday morning I when to start it and pull it into the garage, nothing! After a few seconds a hiss came from under the floor and as I scrambled to disconnect the battery it was to late! The neg. wire had aready parted company from the terminal. From what I gathered I was doing some arc welding down there. The "Question" is what damage did I do so far ??? What caused it ??? The 6 volt battery is taking a charge. The neg. wire to the starter did get quite warm and the terminal in the starter is loose. How should I procede from here??? Thanks to anyone that can help. Jim D.

'54 Chevy 3100, 235 with 3-speed

if the cable was lose on the starter its posible it got shifted enough to ground its self out.I had this happen a couple days ago.The top of the starter glowed orange and the cable was smoking.Itightened the cable on the starter by first tightening a nut on the lug and then puting on a cable and another nut.I had no noticable damage.

Everything electrical or electronic runs on magic and smoke. If you let the smoke out the magic dies.
Dennis

I'm trying to figure out just what happened. Did the positive cable remain connected and intact? And the negative cable came loose?

Start by replacing the negative cable. Also check all connections between the battery and starter. Clean the mating surfaces with sandpaper. It won't hurt to assemble with di-electric grease. Also, check your starter contact, it's on top of the starter where the positive cable connects. Is it heavily burnt? If so, replace it. Only a few bucks. If this doesn't fix it, you will need to check the starter.

It sounds like you had a bad connection, which caused the circuit to need more amperage to do the job. As it worsened, it used more power until it was bad enough to no longer turn the starter and overheated the battery cable.

Like Fred says, Take a close look at those cables to the starter and the ground.Make sure you have clean,tight connections and use a little dielectric grease to keep the out.
Look closely at the frame edges and the body for sharp edges where your positive cable may have grounded out.You probably had a loose or dirty connection on the ground which caused more resistance in the wire.Those little electrons couldn`t take the pressure and had to escape somehow

Thanks Guys, I do remember fooling with the switch terminal a while back. PO had it shimmed with a flat peice of cooper. I ordered a new switch from Carter this morning.

By the way, anybody know where I can get grill fastener kit for '54 Chevy 3100 ? I saw it in one of the catologs last year, but can't find it now.

dabond, very good! I'll have to remember that one.

:confused: howziit guys!

am i reading wrong, when you say the negative battery cable runs to the starter?

isn't your electrical system NEGATIVE ground?

might that be part of your problem....if your actual hook-up is positive-ground/negative-hot? :rolleyes:

In addition to the possibility that the negative cable is not the one that should be going to the starter (I believe early GMC's were positive ground), I saw an article recently talking about the same type of problem you're having. In that case, the battery was also hot and boiling, but it cooked the ground cable as well. The cause of the problem was a poor ground. The owner removed the cables and all ground straps and cleaned the terminal sites. That eliminated the problem.

I think you will find that your starting problems will be cured by replacing all of your big wires (ground straps, starter wire, etc.) with the proper 2/0 size (that's not #2, it's much heavier). The 4 gauge sold for 12 volt systems are way too small and will kill your cranking speed. Your wires should never drop more than 0.5 volt or they are too small. (You can test by hooking your voltmeter across them in volts mode and cranking) If your battery is being cooked then fix your voltage regulator.

I ended up replacing my generator (went south) with a self-exciting 6 volt alternator (Delco 10si with special regulator) and keeping my system six volts. Now it charges at idle, regulates perfectly, and is still mostly original. I can swap the old gen back in by just reversing the bracket and hooking the wires back up to the voltage regulator. It cost me a whopping $25.

On the AD trucks, there is a ground strap that runs from the frame to on of the attach bolts for the starter linkage located just aft of the starter.