Started off like I said with the platform. An MTD 12.5 hp mower that had been stripped of its blown motor. 13bh662f516
Then it was time for battery choice, I really wanted some EV cells but decided to keep it simple and go with 3x group 31, 90AH 12v deep cycles
in series. I had planned to locate 1 in the rear but all 3 fit up front. Leaving room for a potential 48v upgrade. The two battery boxes are fabbed from 3/4 and 1/2" angle iron the upper battery box fits percectly in what was the gas tank area.
Due to the pandemic (I guess) there were no ME motors to be had for less than a small fortune. I had seen people use forklift motors for various projects and when I came across a newly rebuilt 7" 36/48 dc series moto
r I snagged it for a good price. Two things I wish I had thought about before buying this motor * direction of rotation- this motor was built with only 2 external lugs so it was not easily reversed. * shaft size and connection type- the female 5/8 9t spline connection is common among gear pumps and nowhere else! Ended up being cheaper for me to snag a gear pump steal the shaft and grind the gear teeth off. Then because the od was 3/4 i used bronze 3/4" x 1" bushings
to make up the difference. I welded a bearing to the motor mount and hung the shaft off of that at fisr but the e clips and snap rings kept letting go so i made a subframe and support the shaft from below(used some 1" aluminum pipe as a lower shaft since its not really load bearing).
The motor mount is just 1/4" plate chopped up into a big rectangle with an open middle.
The controller is a chinese ripoff of a curtis 1205m
. Didnt touch the programming just using a foot pedal throttle 0-5k that's compatible with the curtis unit.
There is a master switch that breaks the battery circut then also a keyed switch that closes a contactor. Once those two are turned on shes ready to go. Also in line is a 250A fuse
and a shunt. The shunt feeds a Renogy 500A monitor
which is has low alarms that can be set for voltage to prevent excessive rundown.
The electronics are mounted on a plexiglass platform suspended from the hood rails above the motor/ battery.