Hi,
This is about a Craftsman chain drive garage door opener made in 1996.
It stopped working a few days ago, and after disassembling it, it was
obvious that the gear and sprocket needed to be replaced. I did
replace those parts, but after putting everything back under the
ceiling again, the door won't move much anymore.
The chain moves a few inches in one direction, then reverses, moves a
few inches in the other direction and then stops. This occurs
independent of whether the door is locked into the chain, or whether
the chain moves without the door.
Of course, I had to loosen the chain during the installation, so does
this sound like I tightened it too much (or not enough?) when
reinstalling it?
Or could this be a safety "auto reverse" issue? But would that also
explain what happens when the door is disconnected? Are the three
wires that go into in the back of the unit part of the auto reverse
process?
Most importantly, I would of course like to find out how to solve the
problem, so any suggestion would very much be appreciated.
Thanks,
Tim.

wrote in message
oups.com...
Hi,
This is about a Craftsman chain drive garage door opener made in 1996.
It stopped working a few days ago, and after disassembling it, it was
obvious that the gear and sprocket needed to be replaced. I did
replace those parts, but after putting everything back under the
ceiling again, the door won't move much anymore.
The chain moves a few inches in one direction, then reverses, moves a
few inches in the other direction and then stops. This occurs
independent of whether the door is locked into the chain, or whether
the chain moves without the door.
Of course, I had to loosen the chain during the installation, so does
this sound like I tightened it too much (or not enough?) when
reinstalling it?
Or could this be a safety "auto reverse" issue? But would that also
explain what happens when the door is disconnected? Are the three
wires that go into in the back of the unit part of the auto reverse
process?
Most importantly, I would of course like to find out how to solve the
problem, so any suggestion would very much be appreciated.
Thanks,

It is probably a matter of the position of the sprocket on the chain,
which affect the limit switch operation. Or, adjustment issues on the limit
switches or misassembly of the gear/sprocket in relation to the
limit switches.

Bob

On 28 Jan 2007 16:14:17 -0800, wrote:

Hi,
This is about a Craftsman chain drive garage door opener made in 1996.
It stopped working a few days ago, and after disassembling it, it was
obvious that the gear and sprocket needed to be replaced. I did
replace those parts, but after putting everything back under the
ceiling again, the door won't move much anymore.

Did you rotate any of the remaining parts that would appreciably
change the limit setting?. Is the door in the same position after
repairs were completed?

The chain moves a few inches in one direction, then reverses, moves a
few inches in the other direction and then stops. This occurs
independent of whether the door is locked into the chain, or whether
the chain moves without the door.
Of course, I had to loosen the chain during the installation, so does
this sound like I tightened it too much (or not enough?) when
reinstalling it?

It sounds like the bearing on top for the sprocket may be worn out Did
the sprocket actually wear out? Usually the recommended tension on the
chain will destroy the bearing on top before the sprocket.

Or could this be a safety "auto reverse" issue? But would that also
explain what happens when the door is disconnected? Are the three
wires that go into in the back of the unit part of the auto reverse
process?

The three wires on bottom are for up and down limits. Brown-closest to
shaft, gray-middle wire and yellow-farthest from shaft. Why do you ask
about wires? Did you disturb other wiring?

Most importantly, I would of course like to find out how to solve the
problem, so any suggestion would very much be appreciated.
Thanks,
Tim.

It sounds like you left the revolution counter cup (black plastic w/
notches in the side) off or it isn't seated properly on the end of the
motor shaft. This is part of the reversing system & is like a timing
circuit. The board on the end of the motor sends pulses thru the
notches & when the timing of the pulses change (motor slows down) the
door reverses. When this part isn't working properly the door will
move exactly 4" in either direction.

DoorDoc
www.DoorsAndOpeners.com
www.ActionDoor.com

On Jan 28, 7:14 pm, wrote:
Hi,
This is about a Craftsman chain drivegaragedooropenermade in 1996.
It stopped working a few days ago, and after disassembling it, it was
obvious that the gear and sprocket needed to be replaced. I did
replace those parts, but after putting everything back under the
ceiling again, thedoorwon't move much anymore.
The chain moves a few inches in one direction, then reverses, moves a
few inches in the other direction and then stops. This occurs
independent of whether thedooris locked into the chain, or whether
the chain moves without thedoor.
Of course, I had to loosen the chain during the installation, so does
this sound like I tightened it too much (or not enough?) when
reinstalling it?
Or could this be a safety "auto reverse" issue? But would that also
explain what happens when thedooris disconnected? Are the three
wires that go into in the back of the unit part of the auto reverse
process?
Most importantly, I would of course like to find out how to solve the
problem, so any suggestion would very much be appreciated.
Thanks,
Tim.

Wow, I am impressed.....I have to admit that I am guilty as charged.
I did not put the RCC back on......When I reassembled the machine
after changing the gear/sprocket, I must have rotated the gear 120
deg. from its original position, so now the openings for the RCC were
out of place, and it wouldn't fit. In my naivety, I just ignored this,
figuring that a piece of plastic wouldn't matter that much. Was I
wrong.....
Anyway, thank you so much! I really appreciate your help (and of
course, everybody else's ideas), and I will try to fix this then.
Cheers,
Tim.


On Jan 29, 6:44 am, " wrote:
It sounds like you left the revolution counter cup (black plastic w/
notches in the side) off or it isn't seated properly on the end of the
motor shaft. This is part of the reversing system & is like a timing
circuit. The board on the end of the motor sends pulses thru the
notches & when the timing of the pulses change (motor slows down) the
door reverses. When this part isn't working properly the door will
move exactly 4" in either direction.

DoorDocwww.DoorsAndOpeners.comwww.ActionDoor.com

On Jan 28, 7:14 pm, wrote:



Hi,
This is about a Craftsman chain drivegaragedooropenermade in 1996.
It stopped working a few days ago, and after disassembling it, it was
obvious that the gear and sprocket needed to be replaced. I did
replace those parts, but after putting everything back under the
ceiling again, thedoorwon't move much anymore.
The chain moves a few inches in one direction, then reverses, moves a
few inches in the other direction and then stops. This occurs
independent of whether thedooris locked into the chain, or whether
the chain moves without thedoor.
Of course, I had to loosen the chain during the installation, so does
this sound like I tightened it too much (or not enough?) when
reinstalling it?
Or could this be a safety "auto reverse" issue? But would that also
explain what happens when thedooris disconnected? Are the three
wires that go into in the back of the unit part of the auto reverse
process?
Most importantly, I would of course like to find out how to solve the
problem, so any suggestion would very much be appreciated.
Thanks,
Tim.- Hide quoted text -- Show quoted text -