My 20 year old Sears Craftsman 1/3 HP "single" garage door opener has
suddenly become intermittent.
Sometimes the door goes up fine when activated by either the remote or
the wall button, sometimes it goes up one quarter, sometimes half way
and then stops, sometimes it will not go up at all, just jerks a couple
of time as I push the remote, like it wants to, but then stops.
The door once in the up position will always go all the way back down
again. The springs are fine as is the chain and door mechanisms. The
wheels, track and chain are sufficiently greased.
The opener seems to work perfectly once or twice if the AC power cord
has been pulled, and if one wants to open the door, plug the power cord
in and activate the door.
I changed this start cap and the old one gets HOT (and ultimately the
motor) after the door goes up and down a couple of times. I changed
the cap back the the original cold cap, but the door motor just clicks.
Any ideas or suggestions??