OT: Electric Garage Door Opener question

[Thomas Rogers]

One of our 7 year old 1/2 HP Craftsman chain-drive garage door openers went belly-up today. The plastic gear hooked to the main shaft holding the chain sprocket is stripped. I took the cover off the opener and there was a mound of plastic shavings and I could see the stripped gear.



Now it doesn't look like it would be an easy job at all to replace just the gear and I suspect the entire drive unit can be replaced (I wonder if it has a 10 year warranty).



I took the cover off the other opener we had and it is right as rain...no wear at all.



My question is: What could have caused this one to wear and strip like that? Might it have been bound up somewhere? What should I look for other than funny wear spots on the track where it might be rubbing or something? The door has been opening and closing w/out incident.



One thing of note, the bracket that holds the track above the door for this particular door "came loose" a few months back. It was fastened to a 2x4 that was on the wall of the garage, and the whole 2x came loose. I lagged it down when that happened. Might it have bent something when that happened? I don't believe much in coincidence. The fact that the 2x came lose in the first place didn't seem odd. Could something be misaligned on this door causing all the problems?



TJR

 

[Kevin Palmer]

It is designed to fail to prevent other larger issues, (fire, over-heat motors, breaker problems, damaging the garage door etc etc).



It is a fairly common failure and your right, it is not a super easy job to replace. I have done two of them and then bought a new unit.



You want to disconnect the door from the rail and operate it by hand. If it is nice and easy, then I would look at and into the track for issues.



If the door is hard, in either direction, you need to adjust the springs or tension cables and then repair or replace the opener.

 

[Rich Stern]

As CJ infers, the door probably got mechanically bound up by something and the gear sacrificed itself to prevent large scale damage.



I've installed a few of them over the years, but when it comes to major malfunctions in the door hardware, I prefer to call the folks at Overhead Door and let them handle it. I have a lot of respect for the power stored up in those big springs. I had them rebuild the door (new springs, bushings, rollers) two years ago, and it was well worth it.



Side note: I also replaced our very noisy chain drive model when it started to wear out a few years ago. Put a worm drive model in, and I couldn't be happier. So much quieter. We have a guest bedroom over the garage, and I hated opening the door whenever we had people staying at the house. Now it's much, much quieter.

 

[Kevin Palmer]

Rich has a good point.



I had a spring fail and found the spring cost $65.00.



Called a local repair shop and they said they would sell and install for a total of $75.00.



I asked how soon they could get here.



In the process, the took much time in lubricating and adjusting the door, total was like $85.00 and worth every penny simply for the maintenence...

 

[Gavin Allan]

I'd agree. While a garage door is not rocket science, and the springs are not dangerous if you know what you are doing, it is the knowing all the details and having the right equipment and training that makes overhead door work one of those things just better off left to the pros. I can probably do everything that my door needs, and have replaced springs, rollers, and performed adjustments and alignments. However, what might take me four hours to do would be done in 45 minutes by a pro.



BTW: My house has a Murantec M-4700 opener on it. It is by far the QUIETEST opener I have ever heard. No doubt it was not a cheap one, but it has a DC motor, a built in processor with electronic adjustments, LED display, etc. It is so quiet it is uncanny to be in the garage and see the door going up or down, but hardly hear anything. It is 8 years old and has never needed any work or caused any problems. I'd recommend it!

 

[Thomas Rogers]

Thanks for the feedback...The door lowers and closes with ease....it is a very light alumin door without insulation and I can't feel it binding anywhere.



I'm not sure it's worth my time to try to replace just the gear even if I could...that looks like a major pain.



And I don't know if I can get the entire unit (sans track, brackets, chain), delivered to my door, at much less than $129 + tax (cost to buy a whole new opener).



I need a part # from my owners manual and see what Sears Parts hotline says.



Tom

 

[Kevin Palmer]

Sears has a pretty good on line system. You can put in your model number and it will show you a parts blow-up...

 

[Don Pertz]

 

[Don Pertz]

http://cgi.ebay.com/41A2817-Gear-Liftmaster-Sears-Garage-door-opener_W0QQitemZ160104370432QQihZ006QQcategoryZ42364QQrdZ1QQcmdZViewItem



Saw this today, not much time left.

Not sure if its your model.

 

[Thomas Rogers]

DPertz,



Thanks.



The more I read the reviews on this door opener, the more I am happy that I got almost 7 years out of it...seems like cheap Sears crap (my wife bought them for me and had them installed as a Father's day gift).



Read the reviews in the link below:



TJR

 

[Kevin Palmer]

Hey, I recognize that... LOL



Been here done that.



I do not recall how much it was new from Sears. But I do recall I was shocked that it was small money.



I seriously don't recall spending $13.00 on the gear, lube and the mated gear...

 

[Thomas Rogers]

Coastie, how hard is it to replace the gear (I don't think the worm gear is bad, just the disc gear)? What's involved? Taking the unit down, getting the shaft out, etc? It didn't look like getting the shaft out of there was going to be that easy.



I'm thinking of eBaying the part.



TJR

 

[Kevin Palmer]

I did unbolt my main unit and let it rest onto a ladder simply to give me some room. It is not required to do so though.



I recall there was a drift pin. If yours is the same way, you will want a ball peen hammer and a straight sided punch that is close tot eh same size of the pin, not larger and not tapered.



It has been some time but I would say I was totally done in less than a hour from start to finish.



While I had it down, I greased the track and chain up as well.

 

[Thomas Rogers]

Coastie,



Thanks. That's not so bad then. Sounds doable. For under $20 parts I should be able to get another 6 years out of the unit. That's probably worth my time.



TJR

 

[Kevin Palmer]

I got 5 more out of mine and swapped it out just because it was time. My neighbor took it and is still using it to this day. So 2 gears in something like 14 years.



Not too bad.



I STRONGLY suggest you take time to do maintenance on EVERYTHING else as you know you will NEVER do it if you don't.



Make sure the door operates up and down square, (adjust springs or tension cables to square it up). Use while lithium grease on the rollers and tracks. Lube the drive track and chain if you have that style.



You will find that the extra 30 minutes will be WELL worth it.

 

[Thomas Rogers]

BUMP...got the drive gear yesterday in the mail.



Installed it in less than 1.5 hours, and that was with a lot of puttering. Hardest part was getting the chain back on...but even that was pretty easy.



Works like a charm. I took the time to silicone spray the crap out of each of our two doors hinges, rollers, pulleys, and put gobs of grease on the elbow of each inner track, top and bottom of the channel. They are quite a bit quieter now. Also silicone sprayed the rail that the opener rides along.



The ONLY issue I have, and I hope it's a non-issue, is that after getting it all working, I "tinkered". By that I mean I tried to get the door EXACTLY adjusted, adjusted so that the close stop hit with the door compressing with exactly the amount of force I wanted, no less, no more. Over a SHORT period of time I "half-way" opened and closed the door at least a dozen or more times. At some point, it started to go up, and STOPPED. Pressing the remote would just make the unit click (like a relay sound) a couple of times. The motor was toasty...pretty warm.



I assumed that I just overheated it, because after letting it sit a few minutes it started working again just fine. A few more minutes of tinkering and it did it again...wait and it was okay. So either I have a heat problem, or an intermittent problem...I'm hoping heat.



TJR

 

[Kevin Palmer]

I am guessing it was protecting itself. You will need to wait an hour for the motor to cool down to any degree. 10 minutes may be enough to operate the door but it will be right back up to the hot temperature almost instantly as it was not a normally operating temp, it was elivated by probably double or more of what the normal temperature is.