Re: (ET) A Cause of Poor Lift Performance

["Konstanty, Walter (GE Energy Management)" <Walter Konstanty ge com>]

Nick - you have some excellent points here.
  The lift motor was out of a GM Cadillac window motor from what I 
recall..... not exactly made for this duty.
I replaced my lift with a $49 Harbor Freight 2,000lb 12 volt winch by 
removing the bumper and bolting on a piece of channel.  No problem lifting 
anything and can always use the 50' of cable to drag something or get 
unstuck.

Great forum.
...Walt 

-----Original Message-----
From: Nick Skinner [mailto:kc2dzb nycap rr com] 
Sent: Monday, January 26, 2015 9:54 PM
To: elec-trak cosmos phy tufts edu
Subject: (ET) A Cause of Poor Lift Performance

There has been a lot of talk about increasing lift motor voltage to 
compensate for lack of performance. By doing this, I think you're treating 
the symptom and not the real cause.

I have rebuilt several lift units for myself and others. I've have found 
in EVERY single case that the lift shaft bushings are shot. In most cases, 
it was difficult to turn the shaft by hand with the motor removed. In some 
cases, the bushings had seized to the shaft and were turning in the bore 
of the side plate instead. When this is true, upping the voltage is like 
driving a car around with a parking brake that you can't release and 
saying "it's fine, I just press the gas pedal harder".

As part of a rebuild, I always replace the old bushings with new of the 
oilite variety. Depending on the extent of the damage, sometimes the shaft 
requires replacement also. When I'm done with these replacements, you can 
turn the gear with fingertip pressure and roll the shaft effortlessly 
between your index finger and thumb. The proof is in the result. All of 
the units I've rebuilt can lift a snow blower in little over 5 seconds and 
a dozer blade in around 3 with it's original attachment point.

At one point, I modified two lifts to accept sealed ball bearings. One was 
for another owner, and the other is in my E20. My E15 has a stock designed 
lift with oilite bushings and a new shaft. There is virtually no 
performance difference between the two. GE had a good design, but it 
requires maintenance to perform optimally (when was the last time you 
oiled your lift bushings?). Changing to oilite will go a long way to 
reducing this maintenance requirement and the bushings are a few dollars 
each.

If your lift is anemic, I would HIGHLY encourage you to find out WHY 
before resorting to increasing voltage. It just isn't necessary if 
everything is working the way it should.

Nick 


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