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Can I use car batteries on 36v motor and controller?

 I have an old SunL scooter. I want to take the motor and attach it to an outboard drive unit. The motor I have is rated at 36v DC - 29amps. The three batteries I had died. I tried to connect three car batteries in series, I got the 36v but I also got a lot of sparks when I connected up the controller. When I did a direct connect to the motor, no problem, great speed.  Did I use too much amperage and damage the controller? I would like to use the car batteries because they are already on the boat. If it will work, can you suggest a controller unit for my needs and a throttle control.


When connecting any battery pack to the controller there will be a spark so that is normal. A battery pack with a higher Ah rating will not damage the controller. If the original controller and throttle are good then they should work with a larger battery pack. If they are not working then they could be replaced with a 36 Volt controller such as SPD-36800B and any standard throttle that we carry.

Thank you for the quick reply. The controller and motor we have came from a wreck scooter was left outside for awhile. Think, I'll purchase your controller just to be on the safe side.

I appreciate the help.

One other question if you wouldn't mind. Can I place a switch on the power lines to the DC motor to switch the leads, will the motor safely go in reverse?

The motor will run in reverse by changing the polarity of the wires between the motor and controller. There are no safety concerns with running the motor in reverse however for the highest reliability and power output we recommend running it in its forward direction for forwarding vehicle motion and running it in its reverse direction for occasional reversing vehicle motion. 

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