bad battery or what??

[TOMMYHPX4X4]

i have an 08 700 rhino now there is no telling how long the battery was on the shelf before they put it into my rhino but here is my problem when i used to ride the volt meter was always reading 14 volts or over but today i went to pull my next door neighbor's forklift off a trailer and the battery was dead well i jumped it off but afetr riding it around all day i haven't been able to get it to read 14 volts it will go to 14 every so oflten but it mainly stays at 13.9 0r 13.6 could this be a dead cell?? i know it can't bee the charging system because if i rev up the motor the volts go up so i know thats workin any ideas???

 

[MikeD74T]

Hi Tommy
Unless you're reading voltage directly off the battery with an independant meter I'd say you need to clean your connections & spray them with a battery terminal protector. Bad connections at the batery are often overlooked because jumpstarting hits both the battery & wires and after a few seconds of high charge the battery seems to recover. Over the longer term charging gets significantly slowed or stopped at the bad connection. I've also had corrosion problems in block connectors on ATVs that got somewhat submerged that caused intermittant disconnects. Cleaning & silicone dielectric grease helps there.
This may not apply if you don't get into mud/water. MikeD74T

 

[Mickey_Fx]

It's possible you have a bad cell or other moderate resistance short in the electrical path. Short is low enough resistance that the alt can't meet the current demand and as a result the voltage sags.

I'd take some resistance and voltage measurements. Fully charged battery that hasn't seen any current flowing in/out for at least 4 hrs should read 12.7V. Next I'd start taking resistance readings starting at the alt. Don't overlook the possibility of a short in one of the diodes that rectifies the alt AC. Disconnect the battery and turn off all loads and start looking for low resistance path somewhere between the alt and battery.

 

[TOMMYHPX4X4]

it's back to normal again it just acted like that for one day so i don't know what was the problem all the connections are good with no corosion and they are tight ??i guess i'll wiat and see in the mean time i'm gonna make another battery box for a second battery.