I have a 1/2 HP Craftsman garage door opener and the chain has jumped off the sprocket at the opener end. I know this is probably simple to fix, but I can't seem to work it out. I have no manual, as the opener was installed by the previous home owner. I'm trying to avoid having to take the whole thing down to get it working agin.

 

scotty033x,

This should help..it should be similar to what you have - read through it and go from there.

http://www.liftmaster-garage-opener....s/114a2683.pdf

Hope this helps!

 

This is my first time at responding, so somebody stop me if I am wrong.....

This is from memory...but there is a bolt with nuts on it that control the tension of your chain. I believe it is on the bracketure that connects to the door, so you may have to unhook the door and close it by hand just to have access to it. Visually mark the location of one of the nuts (the one on the side opposite to the sproket) of the and then loosen it enough to give you slack and refit the chain to the sprocket. Retighten the nut to the original location, plus maybe another turn or so. If the chain jumped you may have had too much slack. Don't go super tight, the chain is meant to have some sag.

Let me know if this works, if not I'll take a closer look and try to paint you a better picture.

 

Stoney is correct. Just loosen the tightner, and slip thechain back on. Good Luck