its been a great work house for years then all of a sudden lost power would barely move batteries showing 59 volts thought it was my speed controller took it off put another used one one same thing took the. Motor apart replaces the insides same thing I can pick it up with my fork lift a nd it runs like crazy soo as I put it on the ground no power I can't figure it out here are some pics I don't know what kind it is thanks for any help also all 4 points on the motor are 60 volt that can't be right huh I need a wireing diagram bad
From your description of the problem it is most likely that one or more of the batteries has failed and is dropping Voltage under load. The first thing I would do is individually load test each battery with an automotive battery load tester. Load testing the individual batteries will show you which ones are good and which are bad. 59 or 60 Volts is a very low reading for a 60 Volt battery pack. Each battery in the pack should charge up to 13.8 Volts, so the Voltage of the battery pack should be at 69 Volts when fully charged.
Automotive battery load testers can be purchased from harbor freight for around $20.00 or from auto parts stores for a little more.