Sears garage door opener will not stay shut

I have a sears garage opener with a chain and sprocket drive. It is approximately ten years old. Now it closes all the way but then re-opens. I tried to adjust so it did not close so far but adjustment doesn't work. When it opens it opens all the way until it hits the stop nut. The others (3 total) do not do this. It seems it has lost track of how far it is openening. Any ideas would be apreciated!
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Get your family out of that house NOW. It's haunted.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
snipped-for-privacy@mc.net wrote:

About the only thing you can do is to make sure the wires to the top and bottom sensors are both secure. My guess is the control unit is dead.
--
Joseph Meehan

Dia duit
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
snipped-for-privacy@mc.net wrote:

Maybe the door is binding along the sides. Or there could be dirt built up that prevents it from fully closing. Any resistance will cause the safety mechanism to trip and reverse the travel.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Sounds like the down limit is defective. The contact "ear" has broken off the limit switch assembly. Take the cover off and you will see a wire hanging loose at the limit switch assemby with the ear still attached. This is why the unit doesn't stop at the down position and why the adjustment doesn't do anything.
The part number is 41D3452 on openers made from 1986 to the present / openers made before 1986 uses part number 41B2417.
You will find the part at http://www.garagedoorsupply.com/chamberlain-liftmaster.html
This part is very easy to replace.
Rich ===================================Garage Door Parts, LLC 973-472-4818 http://www.garagedoorsupply.com ===================================

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 15 May 2006 04:07:59 -0700, snipped-for-privacy@mc.net wrote (with possible editing):

Another possibility. If it's a chain drive, you may find that one of the two limit rollers clamped to the chain is missing. One of my openers has that happen regularly. It is very close to the rafters and one of the limit rollers regularly bounces up, hits a rafter, and falls off the chain. Until I get around to replacing it, I just wait until it closes, then immediately hit the button. Note, you have to use a manual button, the remote doesn't work.
--
Larry
Email to rapp at lmr dot com
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Are you sure there's nothing (like a broom handle) getting stuck as the door comes down? That was happening to me last week, and it was almost impossible to see even standing right next to the darned thing.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.