----- Original Message -----
Sent: Friday, March 31, 2000 12:36
PM
Subject: (ET) Mower Motors
I have 2 ET mowing decks, and
3 different types of motors on them!
One has 3 motors
approximately 3.25 x 6.5" (above the deck measurements)
The other deck has 2 motors
4.5 x 5.25 " with small boxes on the side, and 1 motor 4.5 x 6.75" with no box on the
side.
Motors I have seen with boxes on the side were for mid mounted
decks. Make sure that the 6.75 tall motor positions the blade at the
proper height. Some decks had the mounting ring on the motor higher,
which changed the blade mounting height. My guess is that the tall motor
on the 2nd deck will have its blade higher. You need to have the correct
blade height, so either the tall motor or both short motors are wrong for this
deck. If you mix and match motors with the same blade position, put the
odd motor in the middle. (Per Bill Gunn of Technical
Service.)
Due to the presence of
repainting, I think the second deck was substantially repaired and has a "mix
and match" motor set since none of the pictures of ETs I've seen has different
motors on a single deck.
(Another Bill Gunnism) Bill
Gunn once said to me that the he liked the larger motors better, but not
why. (More power, longer life?) However, he also said that the
small diameter motors had longer brush life. My deck with three small
diameter (3-1/4 inch diameter) was rebuilt 9 years ago with new
bearings. I did not need brushes. Two days ago I disassembled one
to make sure it was OK, and the brushes and commutator were still within wear
limits. (They were 15/32 to 1/2 inch long. Per Bill Gunn new
brushes are 9/16 long, and worn out brushes are 3/8 long.) The
commutator had no measureable wear, although there was some (normal)
discoloration.
Question: Is one type
of motor better than the others? If so, which? Historically,
what's the progesssion of sizes? Is there any engineering problem with
my "mix and match" set - its worked OK for years.
Also, one deck has a locator
arm (the spring and piston assembly) that is in pieces. While I seem to
have the parts, there is no obvious way to keep the shaft/piston from simply
falling out of the cylinder assembly since there seems to be no retainer, and
no obvious way to get to one internally. I have no diagrams or pictures
in my archives that might be of help - can anyone tell me how to put these
parts back together again?
There should be a round hole on
the side of the outer tube. It is used to install a roll pin through a
hole in the inner shaft. The inner shaft must be pushed in, compressing
the spring, before you can see the hole for the roll pin. It is hard to
compress the spring hard enough by hand to be able to see the roll pin hole,
but with the pieces loose you should be able to see where the pin was
before it failed. (This all assumes GE did not use different assembly
mehtods.)
Pieter Litchfield