Battery Drain

[toyboyttoo]

My John Deere 4710 (2003) had the battery replaced last November but would not hold the charge. I called the dealer who thought it might be a bad battery so we replaced it. Worked fine all summer but wouldn't start the other day. Trickle charged it, the ploughed snow for two hours. Went out this morning and dead again. Could it be another bad battery or do I have a battery drain problem. If a battery drain, where do I start? I don't want to call the dealer if I can fix it.
Thanks for any assistance

 

[murphy1244]

Put a ammeter between the positive post and cable and see if you have a draw.

 

[toyboyttoo]

Thanks, will try.

 

[445A]

Or a test light. If it shows a draw, I'd disconnect the positive wire at the alternator. If it doesn't show a draw, now, you have a bad diode in the rectifier bridge in the alt. It can still show a charging voltage, but it won't have the amps behind it to charge the battery. At this point if you still have a draw, hook the alt. back up and go to the fuse box and start pulling fuses, one at a time. I have found in automotive electrical the glove box or trunk lite doesn't shut off and will drain a battery in less than 24 hours. Happy hunting!:dance1: 445A

 

[murphy1244]

Happy Hunting is right! These can be very fun and frustrating.

 

[Soundguy]

the lamp or a ammeter should be telltale. disconnect wires till draw goes away. last thing you pulled when draw died was the culpret.

 

[toyboyttoo]

Thanks everyone! Once I get it charged, I will plough the snow and then get it into the garage to start looking!

 

[Tx Jim]

I agree to check for voltage drain with a test light but I was taught to disconnect ground not positive cable and insert test light for ground cable to find drain.

 

[k0ua]

I agree to check for voltage drain with a test light but I was taught to disconnect ground not positive cable and insert test light for ground cable to find drain.

Jim, I believe it would work either way. The electrons have to make a circuit for there to be current flow.

 

[sunnyside360]

Jim, I believe it would work either way. The electrons have to make a circuit for there to be current flow.

Absolutely correct!