[scottyb]

Running a cart 12 hours in 3 years is not enough to keep the batts exercised... they must be sitting inactive for extended periods of time and if left in a state of discharge ( even partial) For these extended periods of inactivity, the batteries can become compromised... A Specific gravity meter with a temperature compensating feature is a reliable way to test the batteries health. That is where I would start... these batteries should be test a few hours or even the next day after charging.... charging creates false surface readings... so that's a good place to start. Keep in mind a stock cart will run 90 minutes. Your motor is 2xs the stock motor and your tires are considerably larger both of these will result in reduced run time......