...I know how to properly charge a battery, but this time I wasn’t paying attention and foolishly charged it backwards (don’t ask ), red on neg. and back on pos. I went and got a new battery but this as you might suspect, that didn’t solve my problems. Since the “incident” my C-125 Auto has started once and it ran fine, but most the time the starter just spins (may in reverse?) and doesn’t engage the motor (this is with the new batter). Once and a long while it will engage the motor but it wont start. I have noticed that when just the starter spins, the ignition coil heats up. After a little research, I’m thinking the ignition is bad and needs to be replace but before I do this,

is there a simple way to check to see if the ignition coil is bad?

and what else could wrong / what else could have I fried?

Brett

(wishing I could post anonymously)

Brett your starter is fine its the starter drive on the end of it you mhave to piuul the starter to see it its the thing with teeth on it it has a clutch in it thats slipping

I checked the starter teeth and they are chipped a little on the very end thats meet the fly wheel, but nothing bad or at least not near bad enough to cause it not to start. the starter itself will not engage. It just spins. I tried another battery out of my slightly larger working mower and the starter did engage this time but acted as if it didn't have enough power to start the engine. Is there a fuse somewhere that could have been blown? or is this linking back to the ignition coil? or could it be something else?

Brett

Could you answer a question for me?
Did it work OK before you charged the battery backwards?

yeah it did. it had kind of a hard time firing up, but i just figured that was from it sitting for a year or so. it would at least turn over then.

Did you try to start it while the charger was hooked up backwards, or did you catch it before attempting to start it?
Have you tried hooking a second battery up to it? (with jumper cables)

I caught it before I started it. although while i was away, i cleaned all all the grounds and connections i could find and simply enough, now it does crank and did start. but did i still fry the ignition coil or stator (or anything else) when i charged it backwards?

I doubt that anything would be damaged if you didn't turn the key on. There is a remote possibilty that the rectifier/regulator could be damaged, but I honestly doubt it.
Coils, points, and condensers can function with either polarity, as proven by the old positive ground vehicles, so I can't see where they would have sustained any damage either.
The best thing to do now is check the point gap setting and the condition of the contacts themselves. Make sure all connections at the two ignition coil posts are clean and tight and run the engine for a while. It's normal for a battery ignition coil to get warm/hot while in operation, but not so hot that you can't keep your hand on it.
You can also perform charging system checks to verify the operation.
Here's the first and most simple -*test*-('"):
Does the amp gauge work, and what does it do when you start the engine?

yes the amp gauge does work because it drops a little when I turn the tractor over, but it the goes back to roughly 0 while running.

But does it ever go above zero?
Do you have a multimeter? (AC and DC capable - preferably digital)

don't know. right now i have the oil drained out of it, so i didn't keep it on long or rev it up. I'll let ya know tomorrow after work though. in the mean time thanks for helping me out.

Brett

Like I said before if the starter turns over BUT the engine doesnt thats ba starter drive theres a clutch on it thats not catching some times it will BUT most of the time it want.

I rest my case

TT read his post about the starter turning but not the engine

That's true to a point, Jerry. If there isn't enough power (amperage) getting to the starter motor to "whip" it over quick enough to throw the drive out the helix (spiral) on the shaft, then it will only turn the motor over without engaging the drive in to the flywheel ring gear. Rust on the helix will also prohibit the drive from engaging, as will an oily shaft that has collected dust and dirt, causing it to "gum up".

The "integral solenoid" starters on the P series Onans, Kawasakis, etc. will kick the drive gear in to the flywheel ring gear as soon as the solenoid is energized.

ok, the engine fires up good now, and it does charge with higher rpms. i guess i just got a little freaked out with the whole turn of events. thanks though guys.

Brett