A roadside find.
The blade measures about 17 3/4" end-to-end, so I guess that makes it nominally an 18 inch mower.
I don't have much use for electric lawn mowers -- I don't care for the noise they make, and minding the cord is a nuisance.
The last time I looked into a discarded electric lawnmower, it turned out to be a basket case of the first order. On this mower, at least the blade can be turned, so maybe the machine is recoverable.
Top Cover Removal
At either side of the cover, way down by the handlebar brackets, there's a No. 10 x 5/8" pan head threading screw, No. 2 Phillips recess. Removing those two screws gets one to here.
A big DC motor, and a lot of lawn debris to vacuum up. The commutator and brushes are worn, but they look like they still have service life in them.
I tried powering up the unit, and it does run, but with a nasty vibration.
Blade Condition
It isn't good.
The blade is pretty dull, and somehow that blade looks to me like it's been ground the wrong way -- I'd expect to see the chamfer on the upper edge, not the lower.
Blade Removal
Underneath, a single 1/2"-20, 3/4" A/F (across flats) hex washer-face nut holds the blade onto the motor's spindle.
There's the hex nut (an impact wrench makes short work of getting the nut off), a keyed square washer, a square plastic alignment/shear washer, the blade and the motor's cooling fan. The fan is well and truly seized in place. I doubt that it could be non-destructively removed.
The blade is quite imbalanced. I may look into a replacement blade. I'd like to know whether I'm right about the way the blade is ground.
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A Mystery Feature
There's a loose 1/4"-20 screw eye on the line cord, with no obvious place for it to go to. Presumably, the screw eye should be up on the handlebar somewhere, keeping the line cord out of harm's way. If I replace one of the handlebar fasteners with the screw eye, then the screw eye can do its job, instead of flopping about uselessly.
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And here we are with the screw eye installed at the right side handlebar fastening point.
A ty-wrap is holding the line cord in position. The cord is now held up away from the right side rear wheel; much better.
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Blade Update -- THURSDAY, MAY 9, 2019
I checked with the small engines place in Pickering, and it seems that the manner in which the blade is ground is correct -- with the chamfer on the grass side.
The blade took a lot of grinding to balance it. The blade was measurably wider at one end than the other, and I was at it for quite a while with a 1/4" die grinder to correct the imbalance. I was using a primitive rig for a balance indicator, like so.
That's an 8mm bore x 22mm O.D. ball bearing mounted on an 8mm hanger bolt. It served reasonably well, and I got the blade balanced well enough that the dreadful vibration is gone from the machine.
I imagine that blade balance is quite critical on electric mowers because of the high blade speed. I don't know the rpm figure for this mower, but I suspect that it's well in excess of the 3,000-or-so rpm of a typical four-stroke gasoline engine powered mower. A better balancing tool would be a conical-type balancer, like this one from Amazon. I may just get myself one of those.
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Blade Balancing Done To Near Perfection -- TUESDAY, MAY 21, 2019
The blade balancer arrived today. 'Can't say that I'm impressed with it, but I got it to do the job.
The mower's been sold via Kijiji. One less piece of gear cluttering up the place.
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