volts

[chapy]

I have a problem for all you guru's. My battery went dead and I'm not sure why. When it's at an idle the guage reads dead and as soon as you give it a little gas the guage goes up. I don't think it's the charging system just because of the guage going up when throttled up. But I have been wrong many times before. Anybody have any sugestions?? Do you think its the battery? Or is it the charging system? The battery is soo weak that it won't run the winch or the lights for that matter. There again Lights dim untill you give it some gas and they get bright again. Thanks!! SETH

[Roger S]

Likely a bad battery. If you want to diagnose before you spend $ there's ways to do it. The best time to check a suspect battery is when it's weak/run down, by checking voltage. Not just across the terminals but also cell by cell, if you have a voltmeter and battery caps you can remove. With a couple of old screwdrivers or metal rods/wire with voltmeter leads attached and dipped into adjacent cell fill holes, you should have 1.5 or so volts. The 2 end cells, attach one lead to the post next to it. If you see a low reading that shows a bad cell in the chain and battery is junk.

If you charge a battery before this cell test, it may mask the failing cell. A good battery that's run down but not flat should have still have 12 volts. If it's around 10, that's a good indication of a bad cell.

If you want a less technical test, you could pull up a vehicle with jumper cables, and see how the argo acts and reads on it's gauge.

[chapy]

the guage has only read about 11 at the best I have ever seen it. The battery is only a year old but I guess that doesn't matter. I will do the jumper cable test tommorow. I would do the other test but I don't have a voltmeter. I would like to try to fit a little bigger battery in it next. the battery in it is a 500 cca @ 0 degrees. Not sure I can fit anything bigger. I would settle for about anything at this point. It's hard to plow snow if you can't lift the plow

[racerone3]

most any auto parts store (where your gonna go buy a battery anyway) can load test it for you.

[Matt O.]

Chapy,
It does sound like your battery is bad. One thing to keep a eye on the Big Foot's is the charge fuse. The fuse holder is not sealed and the fuse will corrode and create allot of resistance. The charge fuse is located at the front of the engine a few inches under the head. Front of the engine being the side closest to the head lights.

Hope this helps,

Matt

[liflod]

You should check and clean the connections to the battery before you jump to any conclusions. My ground cable was intermittant and it acted just like a dead battery at times. I got lucky because someone saw it spark when I was trying to start it.

[chapy]

Yep I cleaned every connection, poss and neg before I made the post. I am pretty good about fixing stuff. Just not this time. Anyway I took the batteryto NAPA and they put it on a tester and said it was reading 11 volts and the next thing on the tester said no bad cells. They offered to charge the battery and even droped it off at my house for free. I did buy a 1.5 amp trickle charger that I just plug in when I'm not riding. I do alot of short trips and I don't think the battery had time to charge back up to where it needed to be. I will try the battery again and see what it does. I may go with an on board solar trickle charger or an upgraded charging system.

[Jeff t-boss]

When it's at an idle the guage reads dead and as soon as you give it a little gas the guage goes up

You can pull the questionable battery and hook up a known good battery (No need to run the engine) and see if it drains over night. Some charging systems will not actually charge unless the rpm's are 1000 or above. That might explain your needle jump. Also, if you have a bad regulator/rectifier in the system, these could also cause your problem. If the battery dies over night, it's most likely a bad regulator (diodes) or rectifier. It may charge, but will bleed back when the engine is shut down. Or if you start with a charged battery and it ends up going dead. As long as your needle jumps with rpm increase, you can safely assume that the system is charging. It would all be easier to test if you had a volt tester.