Re: (ET) Small fire and motor overload

On December 29, 2019 10:25:28 AM EST, Charlie <medievalist gmail com> wrote:

Jim might still have some of the square spacers. I once successfully made one from the square head of a giant zip tie, but the one Jim sold Pete was better.

--Charlie

On Sat, Dec 28, 2019, 5:40 PM Chris Zach <cz alembic crystel com> wrote:
Man I am glad I fixed the brakes. Today I went up on the hill behind my
house to pick up some fallen trees. Drove up the 20-30 degree path,
picked up 3 5 foot length logs, drove back down and to the house no problem.

Decided to try 6 logs. Much heavier, but since they were at the top of
the hill it wasn't too big a deal, it's a downhill trip with the load
and I can just put it in L and go down the hill.

Well, got towards the bottom of the hill and smelled smoke. And saw
smoke coming from under the tractor. About this time the motor cut out
and I got to use the brakes to stop the tractor and load. Good news: The
new brake kit allowed me to finish the trip down (in LL, no motor) and
figure out what had happened.

When I checked underneath there was a small fire by the brush studs. It
was then I remembered that the top spacer was broken so I used a short
length of auto coolant hose to act as the spacer. Apparently the motor
side had gotten hot, the lower washer loosened, the coolant hose caught
fire, and the motor shorted itself out.

Dragged it back in with the gas tractor (sans load) and pulled the
motor. Sure enough the rear stud was burned, so for now I took the stud
and insulating spacers out of the E15 motor and fixed the E20 motor.

Will test tomorrow, but it did point out one interesting issue: When
going downhill you are in regen mode and the motor is working just as
hard to charge the batteries. Add a half ton of logs behind you and it's
a pretty significant load.

Speaking of which, is there a source for those insulated washers and the
square spacer? I'm assuming they are high temp plastic or resin to hold
up in the motor.

C

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