RE: (ET) mower motors

["Hazen, Dwight L" <hazen indiana edu>]

Your hand on the motors will tell you if one of them is hotter than the
others. If they are all about the same temperature then the high temp
switch needs to be adjusted. It has a small adjusting screw on it. You
could try field tuning of the switches. Or remove all three and adjust
in a controlled environment (the oven?). 

If one motor is getting hotter find out why. Try moving the motor on the
deck and see if the heat moves with the motor. Sharpen and balance the
blades, remove grass build up. Make sure the wheels and rollers are free
and not worn. 

Also, and this may sound stupid. Make sure all three motors are turning
the same direction! If the wires were reversed during motor replacement
strange thing may happen. 

I have only tripped the switch one time mowing on a 90 degree day in
tall wet grass. 

 Dwight  

Dwight L. Hazen, Indiana University, UITS 
Bloomington, In. 47408-7378
812-855-5367 IP phone 317-278-4014    
hazen indiana edu http://php.ucs.indiana.edu/~hazen/
Ham Radio wb9tlh arrl net http://wb9tlh.ampr.us
 

-----Original Message-----
From: Humphrey Timothy H Contr AFRL/IFEC
[mailto:Timothy Humphrey rl af mil] 
Sent: Wednesday, May 21, 2003 10:26 AM
To: elec-trak cosmos phy tufts edu
Subject: (ET) mower motors

Any thoughts on the mower motors overheating.

My rear discharge deck has three motors that were rebuilt by Bill. All
have
new blades on them, purchased from Bill.

However when I mow the right most motor(view from the seat) seems to
overheat and cut out a lot more often than the other two. The center
motor
cuts out occasionally. The left motor has never quit. Strangely, the
right
motor also has a new switch/breaker assembly. Does anybody have any
ideas.

I have pondered a few thoughts;

The right motor is not broke in yet...not likely.

The switch is not right...not likely, Bill put it on.

The right motor is furthest from the main cord so has the longest
umbilical
lead. Maybe excessive voltage drop? This seems somewhat likely since the
center motor has about half the length and runs for a longer period
before
cutting out.

Even after just a few mowings my damn near deaf ears can pick up the
individual hums of the motors singing their sweet tune in three part
harmony. I know when one has passed out. The current meter shows it too.
The
running motor feels no cooler than the stopped motor.

I was thinking though, maybe it would be a neat idea to have a red/green
led
display for each motor that changes color when the motor drops. My
wife's
hearing is very good but she seems oblivious to the fact that one motor
has
dropped. When two go she knows it. Last night two dropped and she
thought
the tractor needed recharging, so drove it over to the outdoor plug and
let
it drink. Not necessarily a bad thing, but not needed either.

It seems to me that the grass I'm cutting shouldn't drop any of the
motors.
Ambient temp is 70, the grass is moist(internal), not wet(external), and
about 4-5 inches long. I'm cutting it in half. I'll really be in trouble
when summer gets here and the ambient is sitting at 85-90. I'm thinking
of
upgrading all of the motor wiring to a heavier gauge. Maybe 8 or 10, I
think
right now it's 12 at best, maybe even 14. While I'm at it, I'll make all
of
them equal lengths.

We've got a week of rain forecast, so I'll take this opportunity to
switch
over to the new deck also. 

Anybody have any other suggestions?

Stay Charged!

Hump
I5/NY