I have a Sears 1/2 HP crafstman garage opener model 139.53413 which had been working fine since I bought my house 4 years ago. Then it went haywire and wouldn't work anymore. I opened the cover and discovered that the genious design for a plastic gear had been shreded somehow. The worm gear looked fine. I replaced the drive gear and cleaned out the worm gear. I could not replace the worm gear because I couldn't get those darn washers out. Well, after re-installing the gear, the garage worked perfectly again and no more sawdust. This only lasted for 1 week. Now, tonight, one of the coldest nights of the year, it decides to stop again. I open up the cover, and more stupid white sawdust....the gear is stripped again.

What on earth is wrong? Why would it work perfectly then all of a sudded go kaput? It must be off axis somewhere, but everything lines up perfectly. I would replace the worm drive if I could get the washers out, but I don't think a new worm and gear are going to solve the problems.

Is it time for a new garage door opener or could I buy a replacement for this.