Lose + battery terminal --> Fried the coils?

[Guest]

Thursday, I had a pretty well-running bike with the occasional misfire. I decided that I needed to check the points, time the ignition, and then do a carb sync.

The battery appeared to be dead. That's odd, it's only a few months old and I recently replaced the stator, repaired a bunch of grounds, and verified my charging system is in good health. No matter, push start it for now and charge the battery over night.

So I went to work on the points. .014" on both sides, then time it. I had to do some bending and filing on the point sets to get the timing adjustments within the slots, but no matter. I finally got it after a few hours of work. It was pouring rain.

I dried the points off with a hair dryer, started the bike, timed 1/4, then 2/3. I noticed that the timing mark for 2/3 was moving around relative to the fixed mark at a steady RPM. Something's not right there. 1/4 was dead steady and I could adjust it simply enough.

Well, I ignored the 2/3 moving mark issue for the time being, got them adjusted real close, and the bike ran like HELL. Spitting and sputtering constantly.

Got the meter out. Now I observed that the 1/4 point set reads 0 ohms across it with the points OPEN. What the hell? 2/3 did not exhibit this behavior. But 1/4 was still firing, as verified by my timing light. Weird.

Took it riding for 15 minutes. Ran like Hell, terrible. Now both the 1/4 point set and the 2/3 point set read 0 ohms with the points open. Couldn't make sense of it. Pulled the seat and found the + terminal for the battery very, very loose. The screw was backed out by 1/8".

So I have the dead battery on the charger now, but I'm guessing that the loose terminal caused the charging system to over-volt the coils, and now they're both internally shorting to ground. It should be simple enough to verify, just by disconnecting the white and black wires up by the coils and checking for ground continuity. I'll check this out tomorrow, but feel free to mutter insults and suggestions my way.

Frustrated.

-Matt

[posplayr]

good thing you have a volt meter

[lemonshindig]

The plot thickens, traced the continuity to ground through my hot circuits to one fuse in particular.

Time to check the wiring diagram...

[rustybronco]

What happened to your post stating 'both' coils were shorted to ground?

That sure didn't sound logical.


Also, check for improperly assembled wires at the points, improperly assembled insulators and possibley bad condensers. The way it was running makes me think one or more condensers are bad.

Then, after you check all that, figure out why you had to bend the points to get the timing slot? in the middle. Somethings definitely wrong...

[lemonshindig]

What happened to your post stating 'both' coils were shorted to ground?

That sure didn't sound logical.


Also, check for improperly assembled wires at the points, improperly assembled insulators and possibley bad condensers. The way it was running makes me think one or more condensers are bad.

Then, after you check all that, figure out why you had to bend the points to get the timing slot? in the middle. Somethings definitely wrong...

I traced the continuity to ground from the points, through the coils, and all the way back to the fuse box. Pulled all four fuses out and then isolated the short to one circuit in particular. But the way the bike is wired, three branch circuits all connect at the fuse box so this short is going through the entire bike with the fuses in. I've narrowed it down though, I'll find it.

Yes, I agree, there is definitely something else wrong. One problem at a time, though.

[cowboyup3371]

I traced the continuity to ground from the points, through the coils, and all the way back to the fuse box. Pulled all four fuses out and then isolated the short to one circuit in particular. But the way the bike is wired, three branch circuits all connect at the fuse box so this short is going through the entire bike with the fuses in. I've narrowed it down though, I'll find it.

Yes, I agree, there is definitely something else wrong. One problem at a time, though.

This is the way all of the bikes are wired as you'll have your lights, horn/indicators, and ignition routing from the fuse block fed by the main power coming off the battery to the fuse block to the ignition switch and back. Have you grabbed the wiring diagram for your bike off Basscliff's site yet? Sounds like a lot of conjecture here instead of actual tracing and looking at the wiring.

[lemonshindig]

. Have you grabbed the wiring diagram for your bike off Basscliff's site yet? Sounds like a lot of conjecture here instead of actual tracing and looking at the wiring.

No conjecture at all, I traced it from the points to one fused circuit using the wiring diagram and my multimeter a couple of days ago. I am a busy man. Don't worry, I'll get there.

[lemonshindig]

Traced the "short" all the way to the indicating bulbs for both the neutral light and the oil pressure light. Pondered that for a moment and realized that the bike was in neutral and, not running, had no oil pressure.

So what I thought was a short to ground turned out to be... perfectly normal operation. I checked continuity between the + battery cable and ground and got infinite resistance. Only when you switch the key on do the lights come on and load the battery.

I feel like a buffoon. Time to figure out what's really wrong with my ignition.