# Exmark lawn mower conversion



## piotrsko (Dec 9, 2007)

Can't help with the idiot part, my kid is 22 and already thinks that. My mower is 6 HP max on a good day, so 11 rated is way overkill. Means it won't overheat. 48 volts is rated, You can go to 60 - 70 for a couple of minutes. Once again overheat. If you have a motor rebuilder nearby, go visit them. Most have used serviceable motors for cheap.

You don't need much in the way of speed control, a simple relay would work. Worst case switching in and out a couple more or less batteries. Used VFD for a.c. motors would worked all well here if you can stomach the higher voltage battery packs. VFD makes motor selection easier too.

Battery size: figure out how long you need it to run, look at the corresponding motor data sheet for amps and size it for perhaps 20% more. (When the grass good too long maybe). More capacity is good for pack life.

This is a start, pretty soon someone else will chime in saying what a bloody nutcase I am and give you their opinionated guess.


----------



## major (Apr 4, 2008)

Masco said:


> 1. What is the best motor to get? I was thinking that a golf cart motor would be perfect. This is the one I'm considering http://www.buggiesunlimited.com/product.asp?sku=D1168&gclid=COfp85n23cYCFQwYHwod1GYNFw I want it to have plenty of power, but not sure if this motor is a little over engineered or way over engineered.


Off hand I'd say the golf cart motor (6.6" dia) is overkill. Run at 48V, I'm not sure the fan load would keep it from overspeed if a series wound version. SepEx would solve it but need a controller. And then you have the issue of no drive bearing or end bracket. 

For a walk-behind push mower, look for a motor about half as massive.


----------



## Masco (Jul 15, 2015)

I'm removing a 14 hp Kawasaki ice. This is not a typical walk behind, this is an exmark commercial grade mower. It has two blades connected by a belt to the drive, and a 6 speed transmission (5f, 1r). 

I'm ok with a little over kill in the motor power, as I want it to be better than its old ICE self. 

Thanks for the suggestion on finding a shop and getting a rebuilt motor. I'll look into that. 

If there is anyone who has done a conversion befor and knows electrical systems I would love to talk with you since every question answered triggers two more in my head.


----------



## major (Apr 4, 2008)

I didn't realize it was such a large self propelled mower. The 6.6" motor might be about right for power. Got a photo?

Here's a deck we did a few years back. http://www.diyelectriccar.com/forums/showpost.php?p=386568&postcount=10


----------



## Masco (Jul 15, 2015)

major said:


> I didn't realize it was such a large self propelled mower. The 6.6" motor might be about right for power. Got a photo?
> 
> Here's a deck we did a few years back. http://www.diyelectriccar.com/forums/showpost.php?p=386568&postcount=10


 
I don't have a pic handy, but here is a link (only that mine is much older)http://www.exmark.com/products/mowers/walk-behind/metro/metro

The deck you did a few years back is exactly what I want to do, only the motor will be in a slightly different location and I want to use Li-Ion battery pack for power.


----------

