Electric Sears Craftsman

dh1 · 05-02-11, 10:36 PM

This is my first post here and I'd thought I'd start off with my little Electric Sears.
I got this a few yrs back as a rusted out non running old junker from my neighbor, he had 2 of them, said "fix 1 for me and the rest is yours". So that's what I did, gave him a running gas riding mower that cuts grass and what was left over was the start of the project.
Took it all apart cleaned and tried to figure out how to make this thing move with battery power. At the time the only motor I had was a 12volt starter/generator off a 40+yr old Tecumseh gas engine, so I mounted it where the gas engine sat and started to experiment with different voltages, to see what worked and what didn't. Found out the motor spins the wrong way and is not reversible so I put a twist in the belt (fig 8) and got the right rotation at the transaxle. Discovered that 24volts gave enough power to move it along at about the same speed as the gas version. Also discovered that grounding the field terminal gave less power and speed. No controller was going to be used here, only a contractor, so grounding the field gave me a slow speed, 2 speed on the motor, 5sp trany, gave 10 forward and 2 reverse speeds.
Next came batteries, best place to put them was where the motor sits, so I moved the motor to make room for the 2 group 29, 12volt deep cycle batteries and weld in some brackets for them. Figured out where to put everything else. The 12volt contractor horn and lights run off 1 batt. the S/G motor runs off 24volts.
Installed an amp and volt meter (12volt meter measures 1 battery only), amp meter is total draw. Also installed momentary foot switch, main key disconnect, speed selector switch and retained the brake switch which shuts off the motor when brake depressed.
Took it all apart again and painted then reassembled it and pictures show what it is.
This is more of a kids toy but I have used it to haul around a little trailer for yard cleanups.

Performance: it works, 1st gear, tie it it a tree and it will sit there and spin the tires effortlessly, 5th gear reaches top speed in less than 2 seconds. Easily climbs hills.
Run time estimate 3hrs+???
45 minutes non stop use the motor is too hot to put your hand on.
For short little jaunts here and there it's good, for long term non stop running your going to cook the motor.

Charger: I use a 24volt cordless mower battery charger and it works great, shuts off when battery pack charged.

I have done a video of this but can't post a link to it.

Daox · 05-03-11, 08:05 AM

Nice tractor! I like how you were able to tuck the batteries under the hood.

What do you use the tractor for? What gauges do you have there?

As far as the motor goes, you can probably add a blower fan to it and have it suck air through the motor to allow it to handle the higher power output than it was designed for. I've been told as long as you can hold your hand on the motor after running it its okay. If you can't, you're running too hot.

dh1 · 05-03-11, 06:49 PM

Quote:

Originally Posted by Daox

Nice tractor! I like how you were able to tuck the batteries under the hood.

What do you use the tractor for? What gauges do you have there?

As far as the motor goes, you can probably add a blower fan to it and have it suck air through the motor to allow it to handle the higher power output than it was designed for. I've been told as long as you can hold your hand on the motor after running it its okay. If you can't, you're running too hot.

The batteries fit in pretty good, you could get 1 more in there but it would be tight.

I did this conversion to see if I could do it and make it work.

The gauges are just automotive meters, 0to14 for volts and -60,0,+60 for the amps.
Maximum the motor draws is about 60amps, this is from a dead stop, on hi power, 5th gear going uphill. So I figure it's about 1400, 1500watts, 2hp.
Driving on the level it draws about
30amps on low power and
45amps on high power.

The motor is a sealed unit and it does get too hot to put your hand on, so it's days are limited.
Some more pictures including the charger I use.

dh1 · 05-07-11, 09:55 PM

Here's a video of it.

YouTube - Electric Sears Lawn Tractor 1

dh1 · 04-20-14, 02:24 PM

Tractor still works, it is now owned by my Friends kids who are having a blast driving it around.
Current pictures taken today.

jeff5may · 04-20-14, 05:44 PM

I had a similar MTD designed mower. I got it because the rear end went out. I found a new rear end for it for $25 with wheels and tires, put that and a new drivebelt on it, and it mowed grass again for years. Then the deck rusted through and the spindles got loose, so I converted into a mobile welder by rigging a GM alternator to it where the deck was removed. I believe it got used more for tugging carts and for fun than for welding.

Finally, the steering gear stripped out on it, so it got parked. Once the wheels rotted, it became an organ donor for other MTD mowers. When my dad and the scrappers finally hauled it off, the motor still ran. It was about 30 years old.

05-02-11, 10:36 PM	#1
dh1 Helper EcoRenovator Join Date: May 2011 Location: Ont. Canada Posts: 99 Thanks: 14 Thanked 11 Times in 9 Posts	Electric Sears Craftsman This is my first post here and I'd thought I'd start off with my little Electric Sears. I got this a few yrs back as a rusted out non running old junker from my neighbor, he had 2 of them, said "fix 1 for me and the rest is yours". So that's what I did, gave him a running gas riding mower that cuts grass and what was left over was the start of the project. Took it all apart cleaned and tried to figure out how to make this thing move with battery power. At the time the only motor I had was a 12volt starter/generator off a 40+yr old Tecumseh gas engine, so I mounted it where the gas engine sat and started to experiment with different voltages, to see what worked and what didn't. Found out the motor spins the wrong way and is not reversible so I put a twist in the belt (fig 8) and got the right rotation at the transaxle. Discovered that 24volts gave enough power to move it along at about the same speed as the gas version. Also discovered that grounding the field terminal gave less power and speed. No controller was going to be used here, only a contractor, so grounding the field gave me a slow speed, 2 speed on the motor, 5sp trany, gave 10 forward and 2 reverse speeds. Next came batteries, best place to put them was where the motor sits, so I moved the motor to make room for the 2 group 29, 12volt deep cycle batteries and weld in some brackets for them. Figured out where to put everything else. The 12volt contractor horn and lights run off 1 batt. the S/G motor runs off 24volts. Installed an amp and volt meter (12volt meter measures 1 battery only), amp meter is total draw. Also installed momentary foot switch, main key disconnect, speed selector switch and retained the brake switch which shuts off the motor when brake depressed. Took it all apart again and painted then reassembled it and pictures show what it is. This is more of a kids toy but I have used it to haul around a little trailer for yard cleanups. Performance: it works, 1st gear, tie it it a tree and it will sit there and spin the tires effortlessly, 5th gear reaches top speed in less than 2 seconds. Easily climbs hills. Run time estimate 3hrs+??? 45 minutes non stop use the motor is too hot to put your hand on. For short little jaunts here and there it's good, for long term non stop running your going to cook the motor. Charger: I use a 24volt cordless mower battery charger and it works great, shuts off when battery pack charged. I have done a video of this but can't post a link to it. Attached Thumbnails Last edited by Daox; 05-15-14 at 03:43 PM.. Reason: spelling

05-03-11, 08:05 AM	#2
Daox Administrator Join Date: Aug 2008 Location: Germantown, WI Posts: 5,525 Thanks: 1,162 Thanked 374 Times in 305 Posts	Nice tractor! I like how you were able to tuck the batteries under the hood. What do you use the tractor for? What gauges do you have there? As far as the motor goes, you can probably add a blower fan to it and have it suck air through the motor to allow it to handle the higher power output than it was designed for. I've been told as long as you can hold your hand on the motor after running it its okay. If you can't, you're running too hot. __________________ Current project - To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. & To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

04-20-14, 02:24 PM	#5
dh1 Helper EcoRenovator Join Date: May 2011 Location: Ont. Canada Posts: 99 Thanks: 14 Thanked 11 Times in 9 Posts	Update Tractor still works, it is now owned by my Friends kids who are having a blast driving it around. Current pictures taken today. Attached Thumbnails Last edited by Daox; 04-21-14 at 08:48 AM..

04-20-14, 05:44 PM	#6
jeff5may Supreme EcoRenovator Join Date: Jan 2010 Location: elizabethtown, ky, USA Posts: 2,431 Thanks: 431 Thanked 619 Times in 517 Posts	I had a similar MTD designed mower. I got it because the rear end went out. I found a new rear end for it for $25 with wheels and tires, put that and a new drivebelt on it, and it mowed grass again for years. Then the deck rusted through and the spindles got loose, so I converted into a mobile welder by rigging a GM alternator to it where the deck was removed. I believe it got used more for tugging carts and for fun than for welding. Finally, the steering gear stripped out on it, so it got parked. Once the wheels rotted, it became an organ donor for other MTD mowers. When my dad and the scrappers finally hauled it off, the motor still ran. It was about 30 years old.