Spring is in the air, which means that the grass is really starting to grow and I need a way to mow it. Last summer, I acquired an Elec-Trak E15. It even came with a plow! Unfortunately, one of the three mowing deck blade motors was completely seized up, and the other two had a little bit of a rattle to them.
I’d like to get to mowing the lawn with the E15 (and sell my old E10) but first, it means I really need to fix those motors.
Soooooooo, I started by removing the lawn mower blades from each of the motors. Jamming a piece of 2×4 between the blade and the underside of the deck made it easier to take out the blade bolt. Next, I removed the caps on the motors. Under the caps, I could disconnect the two wires going to the motor. I marked the two wires with red and black electrical tape, so I would remember the right way to put them back on. Then, I removed the four bolts holding holding the motors to the deck. (Those were pretty rusty, but I’ve been spraying them with penetration oil every once in a while for the past couple of weeks. That came right off because of it.)
With the motors out, I could start disassembling them on the work-bench. On one end of the motor is the hub that the blade connects to. That would have to be removed from the drive-shaft to be able to take the motor apart. On the opposite end, two small nuts held the brush assembly to the top end of the motor.
I already owned a steering-wheel puller, but needed some way to connect it to the various parts of the motor that I would need to pull. So, I rented a small “bearing splitter” from the local full-service hardware store. I put the splitter behind the blade hub and connected the steering wheel puller to push on the drive-shaft and pull the hub off. Propping the motor up on some bricks made it a little easier to work on.
On the commutator end, I removed the two nuts and pulled off the end cap. This came off the end of the armature fairly easily and revealed the CE bearing and brushes. Two washers and a wiggly washer also immediately fell out. (Note to self: Put those back in before putting it all together!) The brushes looked to be in good condition and the bearing looked just fine as well. The commutator didn’t show any unusual scratches or burns either.
I could now pull out the armature. That’s always just a little tricky on a permanent magnet motor, as the armature will get sucked to the side by the magnets. I just made sure to try to pull it out as gently as I could without scratching up the armature and the magnets against each other.
The drive-end bearing clearly had some corrosion. Not nearly as bad as the one I pulled last summer, from the seized-up motor, but still rattly and not what it should be. I used the puller to remove the bearing in the same way that I pulled the blade hub. The drive-shaft had some rust on it, which I cleaned off by hand with emery cloth.
I also pulled apart the other motor, which was in very similar condition. The brushes were fine, the CE bearing was fine, but the DE bearing could be replaced. I went to the auto parts store (Napa) and bought a 6204 bearing. They only had the one in stock and I had to drive to another Napa store to get the second one. I also don’t own a bearing press, so I didn’t have the “right” way to install the bearing. What I did have was a long 3/4″ socket, which fit right over the drive-shaft and rested directly on the inner race of the bearing. I slid the bearing onto shaft, slide the socket over that, and then with the socket end down, gave the whole assembly a swift slam down onto a piece of scrap wood. The bearing slid right up into place.
Besides the bearings, I also had to create a fix on motor #1. Inside the motor, there are two threaded rods that hold the commutator end down to the shell of the motor. These rods are really what holds the entire motor together, and on motor #1, one of the two rods was broken, snapped short. Fortunately, it wasn’t so short that I couldn’t grab it with a Vise-Grips. I sprayed a little PB-Blaster down into the motor and let it soak in around the rod for a few minutes, and then slowly started turning the rod counter-clockwise. If I was really lucky, the rod would come out. If I wasn’t, it would snap further down and I would have NO way to get it out. Steadily, I kept turning the rod. Looks like I got lucky. It came out without breaking.
I took the rod to the hardware store to find some matching material, and it looked like it was #10 with a fine pitch thread. I added a little anti-seize to the end of the rod before sticking it down into the motor. Then, I again remembered that there are large permanent magnets inside the motor and I had just stuck a steel rod inside. THWACK. The rod stuck straight to the magnet. It was a frustrating next few minutes as I tried to avoid magnetic fields while guiding the thin rod into a tiny hole at the bottom of a very dark motor. Eventually, I did get it in and threaded it into place. I then threaded a nut on the opposite end, past where I would cut, cut the rod to length, and unthreaded the nut back off. That cleans up the thread after it gets mangled from cutting the rod.
With the new bearings in and the rod replaced, it was time to reassemble the motors. Assembly was just the reverse of disassembly, except that I didn’t need a puller. The cleaned and lubricated parts slid together very nicely. The only real trick to it all is that the brushes need to be momentarily pulled back to get the end cap/brush assembly over the CE bearing and onto the commutator.
Next, it was time for some paint. I cleaned the motors off as best I could and wire brushed surface rust and loose paint. I hit all three motors with a coat of gray automotive primer and then two coats of Caterpillar yellow. (If anyone knows which off-the-shelf color is the closest to original Elec-Trak yellow, please let me know.)
I left the motors to dry overnight and then assembled the motors back into the deck, installing the blades (after sharpening), and lastly connected the power wiring. With the mower deck flipped up (so I could see the blades) I spun up power. Looked like all the blades were spinning the right direction! Whoooooo!
Although I’ve had the tractor for almost a year, I haven’t mowed with it yet. Sure, I’ve moved trailers, pushed trucks, and plowed snow all winter, but I hadn’t mowed until NOW. On the first spin around my yard, I was pretty impressed with it. Having the deck in front (instead of mid-mount) lets me mow the grass BEFORE the tires run it over. I can maneuver around trees easier as well. It’s also nice to pull straight forward, stop, and reverse, to trim right up to the mailbox or the side of the house. Compared to the E10, the E15 is bigger, faster, and more fun.
I still have some more work to do on the E15. I never got the keys that went with it, so I had to pull the instrument cluster and literally hot-wire it. It’s also missing the lower electronics cover. For now, I’m just powering it with three old big 12V gel-cell batteries, but in the long-run, I think I want to purchase a good new full set of 6V floodies.
Electric tractors were a good idea 40 years ago, and they are still a good idea today. I’m just feeling pretty good that I’ve figured out enough skills to be able to keep an old machine like this running. And that’s the kind of thing that keeps me charged up!
Take care, and may all your yard-work be fossil-fuel-free!
-Ben
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