I was looking forward to enjoying a day away from the office today on
Presidents Day. Perhaps catching up on reading the three books I've started.

It didn't quite work out that way because when SWMBO and I came home
from an enjoyable evening out last nite and I hit the transmitter to
open the garage door it opened only about halfway and stopped there. I
got out of the car and could hear the opener motor running with a
rasping sound.

Knowing what the inside of the Craftsman opener I installed 24 years ago
looks like, I figured the most likely failure was that the plastic worm
gear drive had given up the ghost. I released the door from the opener,
closed it manually and we went to sleep.

This morning my expectation was confirmed when I removed the opener's
housing and saw the condition of the worm wheel accompanied by a
significant amount of white plastic "sawdust" scattered all around
inside the unit.

The worm wheel looked like this:

http://home.comcast.net/~jwisnia18/temp/toothless.jpg

About half the gear's teeth were about 80 percent worn away and the
remainder were worn so badly they just rubbed against the worm.

I weighed the options: Buy a new opener and an extra transmitter for our
second car for about $175 or see if I could find and buy a replacement
gear set quickly. I figured that if I could get the parts the time I'd
spend putting them into the old opener would be about equal to what I
spend removing that old opener and assembling/installing a new one.

Wonder of wonders, My first phone call located a replacement gear set
kit at a Sears service center not far away and for about $25 I bought a
plastic bag containing a new set of gears, plus a tube of grease for
them and numerous little hardware items to enable fitting the gears into
a wide range of Craftsman/Chamberlain openers.

About an hour after I returned home with the parts the old opener was
working just fine again. I wonder how the original gears would have
fared if I'd thought to grease them a few times during the past 24
years. G

It feels good when things do work out, doesn't it?

Jeff

--
Jeffry Wisnia
(W1BSV + Brass Rat '57 EE)
The speed of light is 1.8*10e12 furlongs per fortnight.