Need some electrical diagnostic help on 125
 

Hi all, new member here, just joined the forum a few days ago, since I picked up a Cub 125.

Here's my problem. Hopefully I've got all the relevant details. So the tractor was needing jumped, when I got it. My uncle (he's West Valley Garden, here on the forum) and I put a meter on the battery, and running the tractor was definitely running the battery down. So ok, we've got some kind of charging issue here, so we started cleaning up electrical connections. We took apart, cleaned, and reconnected:

the wires at the battery terminals
the connections on the starter-generator
the connections on the voltage regulator
the three prong plug connection underneath the gauge panel

We then tried to start the tractor, and the starter generator spun, but didn't turn the engine over. Head-scratching ensued. Noticed, while we're at it, that we're getting some smoke out of what we thought was the ground wire to the voltage regulator.

I've tried disconnecting the voltage regulator, no dice. starter still just spins. followed advice at the link here: https://www.onlycubcadets.net/forum/showthread.php?t=18, steps 1 and 5.

Step 1 tested ok.
When I tried step 5, I got a whole pile of sparks when I touched jumper to the Gen terminal on the V/R. Nothing at all, when I touched jumper wire to the battery connection on the V/R. (more why I skipped step two, below)

At this point, I'm now getting smoke, not only from what I'm pretty sure is the ground wire on the V/R, but also from the positive terminal on the battery. Not good.

Complicating all this, is that the color coding for the wires to the V/R is missing. The wires all have some kind of coating on them, and scraping that off doesn't uncover any color underneath. So these must not be original wires, I suppose. But in any case, we were careful to mark the wires we pulled off the regulator. Also, am not sure if the V/R is original to the tractor, either.

So we've basically got two (I think) layers of problem to solve here.

1. What was the original problem that was causing the battery drain
2. What would potentially cause the new problem of the engine not turning over and smoking wires, which apparently resulted from us cleaning up connection points and putting everything back together.

I'm stumped, :bigthink: hoping the assembled wisdom here can help us out.

Aaron

Broken Belt....???? :bigthink:

Smoke coming from the V/R ??? :bigthink:

I am not understanding what you are saying.

Sounds like the Starter Solenoid is stuck in the on position, or mistakenly energized.

Something is not right here.

(A) Do you have a DVM or a VOM meter, and (B) know how to use it ???

:bigthink:

Broken belt: Belt is fine

Second question: It looks as though smoke is coming out of what I'm pretty sure is the ground wire, to the V/R. I'm also getting smoke coming from the wire at the positive battery terminal

Last question: I've got a cheapie VOM meter. Not real proficient at it, but I can check basic AC and DC voltage with it. So how would I check to see if the starter solenoid is stuck, as you say?

Aaron

Do you know how to check for continuity (Ohms) between two points ??

:bigthink:

I think I should be able to do that, with my voltmeter. If not, I'm going to need to get a better one soon, anyway, so I could just go get a newer digital meter.

Aaron

Most DVM's (or the older VOM) have a Resistance Scale (measures ohms) on them. If you meter does not, I would suggest that you acquire one that does. It doesn't have to be fancy or expensive. Measuring resistance on a Cub Cadet, does not require super accuracy.

don't wanna sound like a ???????? but ohms is the one that looks like a horseshoe symbol on the meter, don't run current through that setting

I too am not sure what you mean by "just spins". Are you saying the starter turns and the motor does not? That would mean either the belt is too loose or broken. Or are you saying both the starter and motor "spin" together?

The starter/generator spins, and spins the belt, but the motor doesn't turn over. When I first got the tractor, you had to jump it, but when you did, it started just fine. This was what got me to wondering if the starter motor could have gotten reversed, in the course of re-attaching wires, and why I attempted to change the polarity on it to check that.

Whn I get home this evening, I will double check which way the pulley is spinning, on the starter motor.

Aaron

is the belt tight? can you turn the motor any at all by hand?