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dh1 · 03-24-12, 07:59 PM

I have this little Blue Sears, this was the first tractor I converted to battery electric drive and I did to see if I could do it.
http://ecorenovator.org/forum/lawn-g...craftsman.html
I have recently picked up another Sears lawn tractor complete working unit identical to the 1st one, even the model#s are the same, it's a 1981 Sears LT11 lawn tractor. The plan is convert this one into a working lawn tractor that cuts grass.
-Basically remove the 11hp gas engine and install an Etek motor in it's place.
-Remove the pulley off the gas engine and put it on the electric motor.
-Mount the electric motor so that the pulley is in the same spot, position as the it was in the gas version. This way all the belts line up, the trans-axle, clutch, mower deck drive and it's clutch all work the same as before.
-Motor needs 48volts, 4 x 12volt batteries to run at 3456rpm. This is almost the same rpms as the 3600rpms gas engine runs at full speed which is what you would run it at to cut your grass.
-There is no need for a controller since the motor will not over rev, at no load it turns 3456rpm, as you increase the load on it draws more current and try's to maintain the same rpms, acts like a governor on a gas engine. This saves an expense in doing the conversion. All you need is a 48volt contactor which you would have to have if you used a controller, basically a big switch to turn the motor on and off.
-The Etek motor I'm using has a 8HP continuous and 15HP peak 1 minute.
-The output shaft on the Etek that I have is 1"dia, 2-7/8" long, most vertical shaft gas engines have a 1"dia, 3" long output shaft on them. This makes the conversion easy as the gas engines pulley fits right on the electric motor.
-The hardest part is going to be where to put the 4, 12volt Batteries, the bigger the batteries, the more amp/hrs, the better, more run time.
Right now I have the tractor and electric motor.
There are many guys who have done this conversion without a controller using similar parts that I am.
The Motenergy ME1004 is the new version of the Etek that I have, it has the same 1" x 3" shaft and is a more powerful motor.
200amps continuous, 12.5hp
400amps for 1 minute, 25hp peak.
at 48volts.
ME1004 Brush-Type DC Motor
Motor Motenergy ME1004 Permanent Magnet DC Pancake Brushed Double Magnet

03-24-12, 07:59 PM	#1
dh1 Helper EcoRenovator Join Date: May 2011 Location: Ont. Canada Posts: 99 Thanks: 14 Thanked 11 Times in 9 Posts	Sears Lawn Tractor EV Conversion I have this little Blue Sears, this was the first tractor I converted to battery electric drive and I did to see if I could do it. http://ecorenovator.org/forum/lawn-g...craftsman.html I have recently picked up another Sears lawn tractor complete working unit identical to the 1st one, even the model#s are the same, it's a 1981 Sears LT11 lawn tractor. The plan is convert this one into a working lawn tractor that cuts grass. -Basically remove the 11hp gas engine and install an Etek motor in it's place. -Remove the pulley off the gas engine and put it on the electric motor. -Mount the electric motor so that the pulley is in the same spot, position as the it was in the gas version. This way all the belts line up, the trans-axle, clutch, mower deck drive and it's clutch all work the same as before. -Motor needs 48volts, 4 x 12volt batteries to run at 3456rpm. This is almost the same rpms as the 3600rpms gas engine runs at full speed which is what you would run it at to cut your grass. -There is no need for a controller since the motor will not over rev, at no load it turns 3456rpm, as you increase the load on it draws more current and try's to maintain the same rpms, acts like a governor on a gas engine. This saves an expense in doing the conversion. All you need is a 48volt contactor which you would have to have if you used a controller, basically a big switch to turn the motor on and off. -The Etek motor I'm using has a 8HP continuous and 15HP peak 1 minute. -The output shaft on the Etek that I have is 1"dia, 2-7/8" long, most vertical shaft gas engines have a 1"dia, 3" long output shaft on them. This makes the conversion easy as the gas engines pulley fits right on the electric motor. -The hardest part is going to be where to put the 4, 12volt Batteries, the bigger the batteries, the more amp/hrs, the better, more run time. Right now I have the tractor and electric motor. There are many guys who have done this conversion without a controller using similar parts that I am. The Motenergy ME1004 is the new version of the Etek that I have, it has the same 1" x 3" shaft and is a more powerful motor. 200amps continuous, 12.5hp 400amps for 1 minute, 25hp peak. at 48volts. ME1004 Brush-Type DC Motor Motor Motenergy ME1004 Permanent Magnet DC Pancake Brushed Double Magnet Attached Images