Our garage door opener started making a thumping noise that got worse, and then it did not want to open our door. It sounded like the sound was coming from within the motor housing, so I figured something was busted bad. Started researching new openers.

I had previously fixed our opener when a chain guide sprocket had broken. Had to order over the internet. I thought I would take the housing apart to see what was wrong before going off to buy a new one. Piece of rubber fell out of the housing. About 5 inches of the inside of the drive belt had torn away. The thumping noise was the stripped part of the belt slipping on the drive wheel.

Ace Hardware. Lots of belts, but not the 3L 290 size. Lowe’s. Lawnmower belts only. Guy there said try Pep Boys, Autozone, or Napa. Pep Boys guy looked at it and brought out something that looked like a close match. Had to adjust the motor a tad for tension and the belt seems a bit too wide, but the garage door is going up and down fine. $12.70 beats $200.

Reference: Original belt is optibelt 3L 290 (H). Made in Germany (like my Passat.) Opener is an Allister II. Replacement belt Dayco Top Cog 15295 (11A0750). Has ribs on the outside where the 3L 290 was smooth. Doesn’t seem to matter. Looks like a much tougher auto belt. Aaargh.