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54 GMC 100 series 12-volt system

My starter won’t turn over and I’m wondering if the starter has gone out, would appreciate any tips.

For some period of time, it has been difficult to get the starter to turn over. I would depress the foot switch and nothing would happen. If I depress release depress release several time, it would eventually “catch” and crank the engine.

Yesterday it would never catch. I took the foot start switch off and touched the cable directly to the copper contact on the top of the starter, nothing happened. Thinking that perhaps the cable was bad, I used jumper cables to make the connection. One end on the positive side and the other side I touched to the copper contact, again nothing happened. Makes me think the starter is dead, is it? Any additional test I should try?

If I need to purchase a new starter, should I go with a 12 or 6 volt?

As a side note, not sure this as anything to do with it but… The foot switch was somewhat difficult to depress but yesterday it got a whole lot easier to depress. Right before it got easier, I felt something give, had to describe exactly what it was, but it is easier. Looked around and found nothing out of the ordinary. And since I have bypassed the foot switch, I don’t think it is connected.

I'm not clear what the starter is doing. Does it spin but not turn the motor, or does it do nothing?

When my '55 1st's starter failed I replaced it with a 12 volt with a selenoid and installed an ignition switch with a start position.

The starter peddle both operates a switch to put power to the starter and moves the starter drive into mesh with the flywheel.

If the starter turns, but does not turn the motor, check that the drive is being engaged with the flywheel, and that the drive and flywheel still have teeth.

HTH!

Sorry I was not clear.

You depress the foot switch and the starter does not start up. The gear does go in to make contact with the flywheel.

A 6 volt starter will work in a 12 volt electrical system. But, if you have a truck converted to a 12 volt system, you might want to go with a 12 volt starter motor--and they are available for the mechanical shift starter (that is the technical term for the foot-stomper, masher, foot-pedal, or whatever-you-wanna-call-it type of starter on your old Chevy).

Do you know for sure that your starter motor is indeed a 6 volt starter? If it is, the conversion to a 12 volt system may have lead over time to some breakdown internally in the starter motor due to 12 volts coursing through the contacts and brushes.

Do you have lights, heater motor, everything else?

Zero power through the starter motor could be a bad ground somewhere between the hot side connection to the starter motor and the gounding battery post, either poor connection to the frame, or a poor cable/strap connection between the frame and the gounding battery post.

When you removed the electrical switch off the top of the starter motor (I presume you disconnected the hot side battery cable at the battery), and jumped from the hot battery post to the copper contact on top of the starter motor, was this with or without the starter engaged? In other words, did you have somebody in the cab mashing the starter pedal? If yes, you were testing the starter motor under load. If no, then you were testing without any significant load on the starter motor, and the following applies.

If mobody was mashing on the starter pedal, then the starter motor was not engaged with the flywheel, and the starter motor should spin freely with the direct connection. Did you see any spark or electrical arc when you did the direct connection?

If you get a spark or electrical arc, then you are electrically connected through the starter motor to ground. However, if you get a healthy arc and the starter motor does not spin, then its likely something is very wrong--like a significant short.

If you get no spark, then there is an open circuit/wire someplace--wire, brushes, commutator.
Open circuit is better, cause you can fix it easier.

Mashing the starter pedal with you foot and getting no electrical power through the starter motor is a fairly common failing in older Chevys.

You are on the right track with your diagnosis,and if you confirm that the starter motor will not spin, it sounds like the problem is internal with the starter motor.

Quick approach, if you KNOW the battery is good, is a starter motor replacement. If you feel adventurous, pull the starter motor out, give it the direct-connection bench test with the 6 volt battery. If it refuses to spin like a top, dismantle it, clean the commutator, and replace the brushes--not a difficult job, but just make sure none of the copper leads end up touching the starter motor case when you reassemble everything.

Don't listen to some of these feller that tell you to swap out your stomper starter with a solenoid type.

Despite what anyone says, that doesn't make it any easier to start you Chevy, won't make it go faster, and it's a whole lot less fun.

It sounds like you have a bad winding on the starter armature. If the starter stops on this spot, it will catch after repeated 'bumps' on the starter switch - or maybe not catch at all!

The starter switch issue IS a coincidence however. If you are certain you are bypassing the starter switch correctly, I'd pull the started and get it checked at a shop. You can also just cut to the chase and get a rebuilt rebuilt starter.

Unless a connecting wire is obviously broken, you can't diagnose a armature winding issue easily at home.