6 volt Starter Help

[54blackhornet]

I am trying to start a GMC 1 ton that has sat for about 10 years. It has a 235 chevy in place of the original 228. The po said it ran fine when he parked it, installed new battery, 1g cables, ran negative cable straight to one of the bolts holding the starter in place to ensure a good ground. When i turn the key the light come on fine, amp gauge shows discharge but nothing happens when i step on the starter peddle on the floor?
I even went under the hood and pushed in the button on the starter that the peddle pushes on from inside, Nothing not even a sound of any kind. The truck has sat untouched in dry Easter Oregon, no rust no humidity. All other accessorys seem to work fine. I was going to pull starter but figured I would ask you guy's first......Thanks.........

[OrrieG]

Can you jump the wire connections to the button (solenoid I assume)? You might try lightly tapping the starter housing too, brushes might be a little stuck. Stovebolt guys might have some ideas too.

[54blackhornet]

Thanks I will try the big hammer on it

[dwcsr]

Maybe someone will chime in on this but I believe 6V GMC was a Positive ground system. Chevy was 6v negative. Go over to the stovebolt.com site and ask there.

[OrrieG]

yes it is I blew up a perfectly good radio wiring it to my dads 57 gmc bus in the 60's. At Stove bolt there is a tech article on how to convert to pos ground, pretty easy, reverse the coil and ammeter wires, and battery cables.

[54blackhornet]

Thanks a lot guy's for the tip about + ground , when it would not start I tryed to jump it with a 12 volt battery for added amps and got a lot of sparks? so i just stoped untill i asked u guy's for some help, I will research further and let you know

[Fred T]

With the mechanical starter linkage there isn't much that can go wrong. If you have voltage to the starter, first check the switch (the button on top of the starter). It comes off with 2 screws, iirc. Look at the contacts inside and check to insure the contacts are engaging. Usually the contacts get burnt from use. You should be able to buy a new switch at a local parts store.

If that is not your problem, then something is wrong inside your starter. Usually a new set of brushes will fix that. We used to replace them regularly when these trucks were active. When the brushes get worn too far, they no longer make contact and you have a dead starter.

These repairs are fairly easy. The factory shop manual shows how to repair the starter. They are found on-line at http://chevy.oldcarmanualproject.com/ For the 6 volt mechanical linkage starter look in the 48-51 Chevy truck shop manual.

[54blackhornet]

Fred,
Thanks for the insight. I am going to pull the starter Monday and take it to a friend who has worked on auto electrics for about the last 50 years. He told me you should never jump a 6 volt system with a 12 volt battery unless the 6 volt vehicle is turning over already, contrary to what others have suggested

[Fred T]

You won't hurt anything by jumping as long as the starter doesn't get hot. Always limit your starter time to 15 seconds, then take a break. I have about 30,000 miles with a 6 volt starter on a 12 volt system. Had to replace the brushes recently, which isn't bad.