Farmall Cub

' 52 CUB running good in this fine clean up weather. However.... still trying to figure out why ammeter shows in" CHARGE " area when the lights are turned " ON. " Also, when starting, the starter sometimes hesitates before cranking starts. A few times it "grunts", then it either turns over, or maybe not. Battery and coil are new. Thought's ??

The starter itself or its connections back to the battery need serviced. Try servicing all the connections first.

Does the ammeter move to charge when the lights are turned on with the engine stopped or running?

6 volt electrical system. Battery positive ground?

Take the band off the starter and see if the brushes are shot if not broke in half. Also could be cable time as well.

yes, 6 volt, positive ground, and ammeter shows charge when lights are turned on and engine stopped or running. my son - in law put a new coil on. what happens if wires could be on backwards. I will CHECK OUT THE STARTER as suggested. thank you.

dhart wrote:yes, 6 volt, positive ground, and ammeter shows charge when lights are turned on and engine stopped or running. my son - in law put a new coil on. what happens if wires could be on backwards. I will CHECK OUT THE STARTER as suggested. thank you.

What happens when the wires are reversed is the ammeter will show a charge when the lights are on.

Denny Clayton wrote:

dhart wrote:yes, 6 volt, positive ground, and ammeter shows charge when lights are turned on and engine stopped or running. my son - in law put a new coil on. what happens if wires could be on backwards. I will CHECK OUT THE STARTER as suggested. thank you.

What happens when the wires are reversed is the ammeter will show a charge when the lights are on.

I read that as the wires at the ignition coil could be reversed. Reversing the wires on the coil will not have a different effect in the electrical generating circuit or direction the amp meter needle moves.

Was the amp meter changed out or the wires on the amp meter removed and then reinstalled?

Multimeter at battery. Check to see that the generator is charging correctly as per the battery polarity. Battery positive terminal grounded. If so exchange wires on the back of the amp gauge.

The other thing you could do is to negative ground the battery and then repolarize the regulator.

Does the ammeter needle move at all or does it stay in one position?

ammeter needle does move around. sometimes to charge. sometimes slight discharge. battery is new so should'nt show too much change. maybe it is just cleaning up the connection's on everything. I do wonder though why needle jumps way over to charge when lights are turned on.

If the power supply to the light switch is on the battery connection at the starter, that would make the generator (with engine running) increase the amperage in order to power the lights without draining the battery. And the ammeter would show that. But if the engine was stopped, that hookup would not move the ammeter at all if the lights were turned on- because the current is not flowing through the ammeter. Normally, turning on the lights with the engine running causes the ammeter to show a lesser charge rate (with the 6 volt systems) because the generator has limited output amperes and the lights are using most of that before it gets to the ammeter.
With the proper (original schematic) electrical system, turning on the lights with the engine stopped shows a significant discharge rate on the ammeter.
I suspect that someone prior to your ownership did some creative (that is not a compliment) alterations to the electrical system.

The original Cub wiring was such that the ammeter shows net amperes going to and from the battery, not necessarily what the generator was producing at the moment.

The owner of this tractor has not posted back regarding findings/progress, if any. Thinking about this again, the power supply connection for the lights, and perhaps the ignition, could have been switched to the battery post on the starter OR to the post on the ammeter that connects to the battery post to recharge the battery. Might be as simple as just moving a wire terminal from one post on the ammeter to the other. Evidently his tractor does not have a voltage regulator with a lighting terminal in use.
Since he reports no electrical problems at this time other than the ammeter readings, the system apparently works for properly recharging the battery. And could continue to do so for a long time into the future. But the operator is not getting the best information from the ammeter about the present performance of the system.
An analog voltmeter at the battery can test for proper voltage output of the generator (and regulator, if there is one).

Been kind of busy lately, and missed the beginning of this thread. If the ammeter shows charge when you speed the engine up, but drops back to the center or close to it when you turn the lights on, that is pretty much normal. The lights draw approximately 2.8 amps each, so if all are on bright, you are drawing 8.4 amps. Standard on a cub generator if they are in top shape is only 11 amps on the earlier ones, less if the brushes are worn or out of adjustment, etc. So you should not expect to see more than a 2 amp or so charge when running at full throttle with the lights on, and that is not much needle movement.

Thank you BUSDRIVER and ALL others. Gave up and gave '52 cub with ammeter questions to local mechanic. If solution is noteworthy, will post his findings.

I hope it all works out well. Many of the mechanics today were born long after alternators became the norm, witnessed by the fact that this Cub owner started out posting about his alternator.
Unless the mechanic is familiar with the generator/cutout/regulator systems, he will either just give up, just start swapping parts, or spend time educating himself. The tuition bill can be steep.