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Topic: KA proline disassembled (3 msgs / 77 lines)
1) From: Gregg Gruen
I completely disassembled my KA Proline grinder over the past week.  I 
know there's been some discussion of this machine in the past, so I
figured I'd tell what I saw in case any of you might be wondering what's inside.
I had taken it down for a cleaning, and when I tipped it on it's back
to get some of the grit out, I noticed it leaking oil out the back. I'd
seen it do that before, but this time there was more.  It has (or had) a
couple of months left on the warranty, but I really wanted to know what
it had inside so I figured I'd peek in the back, and next thing I knew I
had the whole thing in pieces.
The motor-It's a motor made by Johnson, 120DC, about 180W.  According to
the spec sheet it's typically used in things like vacuums.   Those
little plastic nubs you see underneath are holding the circuit board for
the rectifier in place.  It seems to be of pretty high quality
construction compared to boards I've seen in other household
appliances.  
The motor spins pretty fast-almost 9000rpm if you use it at the rated
load.  Taking that speed down is a nice heavy duty planetary gearbox
that's screwed directly to the face of the motor.  The gearbox case is
plastic, as are all the gears.  It's pretty heavy duty stuff, probably a
nylon or something similar.  The source of the oil became apparent
pretty quickly-some of the grease in the gearbox had broken down over
time and pooled under the motor in the casing.  It then runs out the
back when it's tipped.  The gearbox was just packed full of grease, so
there wasn't any chance of it running dry.  The output of the gearbox
was the D-shaped plug that the auger shaft slides into.  There's a felt
washer on that end inside the gearbox that supposedly keeps oil out of
the shaft, but I've found bits of grease around that from time to
time.  
I cleaned a good portion of the gears and casing and repacked it with
food grade grease, and put it all back together.  The new grease is a
little thicker than the stuff they used, so I hear the motor run a
little slower at take off but it picks up ok.  Hopefully this stuff
won't break down as fast.  
-Gregg

2) From: Rich
Think of grease as a sponge full of oil, it is supposed to run out of the sponge.  If it does not then you 
will have no lubrication.  Also, plastic requires special grease and oil.  The regular petroleum based 
lubricants will cause most plastics to become brittle and crack/bust.  Verify that the 'food grade' 
grease you used is rated for the type of plastic you are dealing with.  When it fails the warrantee will 
have expired....
On Fri, 18 May 2007 17:37:52 -0400, Gregg Gruen wrote:
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3) From: raymanowen
"The new grease is a little thicker than the stuff they used, so
I hear the motor run a little slower at take off but it picks up ok.
Hopefully this stuff won't break down as fast."
Your best bet would be to match the original lubricant used by the
manufacturer. They might have used the same stuff in other K-A mixer gear
boxes. K-A might be so kind as to tell what is the right stuff.
If the lubricant was "broken down," were the gears wiped out? The one
follows the other.
Cheers -RayO, aka Opa!
I haven't failed, I have just found 10,000 ways that won't work - -Thomas A.
Edison


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