Garage Door Gear Replacement on LiftMaster Craftsman Openers - Broken Gear and Sprocket Replacement

Garage Door Gear Replacement on LiftMaster Craftsman Openers - Broken Gear and Sprocket Replacement
Garage Door Replacement Gear and Sprocket Kit: amzn.to/3JSpj1A
Vice Grip: amzn.to/3qKsrW5
Recently my garage door stopped opening but the motor was still able to run. This is caused by a stripped out gear inside the motor housing. And in this video I'll show you step-by-step how to fix it yourself! On the front and back, only the bottom screws need to be taken out. But once the cover is off I see a pile of what looks like plastic shavings. This definitely shouldn't be there! On the other side, the main sprocket is completely shredded! There's practically no teeth left on this gear! So it needs to be replaced. I was able to easily find the part on Amazon for just under $20.
And I recommend buying the entire assembly like this rather than just the gear itself. Mainly because this part is easier to install with fewer steps. So start by disconnecting the door from the motor. And on the track the chain needs to be loosened. Use some vice grips to mark the trolley in it's current position. Now loosen and unscrew the nut closest to the garage door. The other nut on the motor side needs to stay in place so don't move that one. There's actually a lot of tension on the chain so it takes awhile before it's loose enough to use my fingers. But this nut needs to be twisted almost all the way to the end and it's not necessary to take it all the way off.
Now take off the cap on the chain sprocket and remove the chain. There are three screws that need to come out but they can only be accessed from inside the motor housing. However, I need to remove the small worm gear by first taking off the 3-prong retaining clip. With a 5/16 nutdriver, I'll take out two of the screws I can directly access with this tool. The third one is blocked by other components so the nutdriver won't work on that one. But you'll need a socket for the 3rd screw. Once I've taken out the last screw, the gear can be lifted out. Even though the replacement comes with lots of parts, I'm only going to use the sprocket assembly and grease.
Before installing the new part, remove the retaining clip and small gear on the bottom. One thing you need to know is that the three screw holes aren't threaded. So I'm going to use the existing screws and cut screw threads into the metal. When all three are done, take them back out. Now I'll apply a liberal amount of grease on the main gear. With the main sprocket greased up, I can insert it back into the motor housing.
Up on top, line up the screw holes and make sure the two rectangular openings face the front and back of the garage. I'll then reattach the small worm gear I removed earlier. And just to make things operate smoothly, I'll apply some grease on this gear as well! Ok now I'm going to start reassembling everything by putting the mounting screws back in. The first two screws are easy with my nutdriver but remember you'll need a socket for the 3rd screw.
Ok with the sprocket assembly secured, I can reattach the chain. When hooking the chain back up, I'm watching to make sure the trolley is against the vice grip before it goes over the gear. At this point, I can now tighten the nut that's closest to the garage door. Remember to leave the other nut in place. With this chain, I tried to keep it in the same position as it was when I removed it. But once I got it fully tightened, I the trolley was about an inch away from my vice grip. I don't think this is a problem because it should be close enough.
Now I'll plug the garage door opener back in and give it a test. At this point it's working great! I can now replace the cap over the chain gear and reconnect the door to the motor. Finish up by reattaching the cover on the motor and the repair is pretty much done! I've listed the replacement parts here in the description so it's easy for you to find! This is a moderate level DIY project. But I'd still say most of you should be able to do this and save some money. If this video was helpful please give me a thumbs up and hit the subscribe button to stay up to date on all my DIY repair videos!
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[@guitar1950]

Excellent instructions. One suggestion though, please don't use pliers to remove nuts! You'll strip the edges of the nuts and make it difficult to remove them if ever needed. Use two small adjustable wrenches or appropriate sized wrenches.

[@brianhalton5913]

I can't thank you enough for posting this clear, concise video for fixing a Craftsman garge door opener. You saved me a couple hundred dollars!

[@lou08071]

Thank you !!! the same thing happened to me.... I followed your steps and it worked! There's no way I would have been able to figure this out let alone fix it without your clear concise video...again , a huge Thank You!

[@digitalcamproducer]

You’re welcome! Glad my instructions were clear enough for you to follow along and make your own repair! Thanks for watching!

[@joeniman2428]

This video was so well done. Often times I find a video with good directions, but it's way longer than necessary. This was short, sweet and nicely narrated. I'm surprised there's not an advertisement. I'd be happy to watch if it helped the author make a little money. Thanks for posting, just ordered my new gear kit. PS - I think it would be worth adding a note on how to properly set the chain tension. If it's too tight, you might wreck your new gear.

[@jeffboyd8129]

The mechanic didn't offer this solution. He said I needed a new opener. My sprocket set comes in tomorrow and I will be doing this job myself. Thank you for this information tutorial.

[@terry7893]

FINALLY! A great video on youTube that gets to the point and doesn't blab on for 18 minutes for 2 minutes worth of content. Grrrrreat video!

[@digitalcamproducer]

Excellent! Glad my video helped! I always try to make my videos as short as possible without adding any unrelated content. Makes everyone happier! Thanks for watching!

[@robertlee4172]

Cool! I fried mine earlier today. The exact model as you have. I'm going to be trouble shooting the thing next week, when it gets warmer.(De 19/2023) Thanks for the Amazon part number. Saves me the trouble.

[@user-bw5vg9uo5g]

Great video. Was able to repair my 20 year old Craftsman garage door opener for less than $20! Thank you!

[@thedodif]

We moved into our house in 2012, and it had this exact garage door opener that was from when the house was built, 1999. Never worked but could hear the motor running. Finally figured I'd watch some videos and found this. Bought parts from Amazon for $15, and did your step by step instructions and now works like a charm! Amazing! You saved me a bunch of money sir. 👏👏👏👏

[@digitalcamproducer]

Excellent! So glad you got your garage door opener fixed. Such a nice feeling saving money doing it yourself! Nice work! Thanks for watching!

[@kbreezy2572]

All I can say is WOW! And thank you for sharing! Very helpful and instructions were spot on! Much appreciated!

[@fong.justinm]

Thanks for for this video. My nylon gears did not wear out, but the sprocket snapped off the chain shaft. Still waiting for my part to come in.

[@jonm2416]

This is exactly what happened to me just now. I'll try this repair bc the opener itself is good quality and lasted 20 years already.

[@darens1926]

That Caddy though!!! Great video!

[@digitalcamproducer]

Yes! My dad’s 1977 Coupe De Ville. Still drives it today! Thanks for watching!

[@Person-jy4sc]

You rock brother, thank you

[@digitalcamproducer]

Thanks! Glad my garage motor repair video was helpful!

[@Bikun500]

I have done this before once but as a reminder I watched this video. One of the best review videos I have watched, very professional, details and the view of the process how you were perform. Very well done, thank you.

[@lorenneil8176]

This was so easy to follow! Thank you so much!! My door is back in operation!!

[@toomuchwelding1013]

I've had the parts for a year but didn't know exactly how it went together, now I'm confident it'll be fixed tomorrow!

[@digitalcamproducer]

Excellent! You’ve got the parts and now you have an instruction video. Yes! Your garage door opener will be fixed soon! Thanks for watching!

[@toomuchwelding1013]

@@digitalcamproducer it's fixed!

[@RobinSingh]

Wow! Saw this after I had my garage door fixed … could have done this! … next time. Thanks for an awesome tutorial.

[@digitalcamproducer]

Yeah it’s not too difficult to do! At least next time you’ll know how to replace the gear yourself! Thanks for watching!

[@thezirons]

Thanks for posting this, made the job easy and quick!

[@ryandewald1]

Thank you. Exactly what I needed. Love your presentation.

[@cjb7702]

Thank you for this video. I was able to fix my opener for less than $20 thanks to your excellent instruction. Much appreciated!

[@digitalcamproducer]

You’re welcome! So glad you were able to fix your garage door opener! Really nice when you only have to pay for the part! Thanks for watching!

[@PaulMason-jd3zo]

Extremely helpful and useful video. Thanks for sharing.

[@GregPapaG]

Thanks! Great Video.. will be using this as a guide for my own repair.

[@digitalcamproducer]

I’m really glad you enjoyed my video! I hope my instructions are clear enough for you to follow along to make your own repair on your garage door opener! Also I really appreciate the donation! It means a lot to me! Thanks for watching!

[@mzendig]

Thanks for this! It saved me about $1000! Took me wayyyyyy longer than you but worth it.

[@deaflumberjack7305]

Great tutorial. If I didn’t have big fat hands I would’ve been done much quicker, but that 3rd screw on the sprocket mount was a pain. I looked up 10 different videos and only yours had a thorough and quick step by step that explained it all quickly. Thanks!

[@digitalcamproducer]

You’re welcome! Glad you got your garage door sprocket replaced! I try to make my videos as detailed as possible partly for me in case I have to do this repair again. But also so viewers like you can see exactly what I’m doing. I like to get close ups so it’s like you’re looking at the process through my eyes! Nice work! Thanks for watching!

[@michaelgkrantz]

Thank you for posting this. It definitely helped me.

[@NoSuffix]

Thanks for the video! It helped a lot in my DIY repairing of the garage opener in which the sprocket shaft totally snapped off 2 days ago. In my Craftsman model, there are two screws that are hard to reach and have to be loosened/tightened by a wrench. Oh man, that took some patience. But now the opener is working properly as it is supposed to be. Still much easier than dissembling all other parts in the opener as instructed in the repair manual coming with the replacement parts.

[@elijahcanup63]

Extremely grateful for this. Thank you!

[@digitalcamproducer]

You’re welcome! So glad my instructions helped! Thanks for watching!

[@georgefleming4956]

What a great tutorial. Can’t thank you enough. New subscriber!

[@digitalcamproducer]

You’re welcome! Glad my garage motor gear replacement tutorial was helpful! And thanks for subscribing! I really appreciate it!

[@davedunbar8884]

Hey, excellent video! Well done, with all the necessary details, but without droning on for half an hour. My 23-yr-old Sears just lost its gear 2 days ago, and I wasn't sure if I could do it -- but now I'm confident I can. Thank you!

[@digitalcamproducer]

Excellent! Glad my video was able to give you the confidence to do the gear replacement yourself! It’s not difficult to do. I was a bit intimidated by the chain part but that went ok with no problem. Thanks for watching!

[@davedunbar8884]

@@digitalcamproducer yes, i did get it done, and it works. mine's a belt, not a chain, but same idea. the belt did give me a little grief, but not too bad, and it's all set now. 🙂

[@thegrognard]

You saved me a ton of $$$. I'm going to make it seem like it is an afternoon-long, 10-beer project; and then look like a miracle-worker a la Scotty on Star Trek. 🖖

[@digitalcamproducer]

Nice work! Star Fleet would be proud! Glad you got your garage door working again!

[@capthindgrinder3072]

Thanks for the instructional . Works well now.

[@maxrockatansky1271]

thanks for the help bud

[@harryjames4988]

Thank you so much,, that was very easy following your instructions..

[@KrisKelly1970]

Thank you so much for the help!

[@digitalcamproducer]

You’re welcome! Glad my garage door gear replacement tutorial helped! Thanks for watching!

[@heatheradams5219]

Thank you so much!!! Most helpful!

[@giotor5603]

Fantastic tutorial! Fortunately, I was able to manage that tough screw with a ratchet. An unexpected surprise near the end when the inner trolley would not align with outer trolley. But I successfully resolved this issue by adjusting the door arm

[@digitalcamproducer]

Yes! A ratchet is the right tool for that one screw inside the housing. Glad you got everything back up and working again! Nice to be able to do fixes like this yourself! Thanks for watching!

[@KJC63]

perfect video...thank so much, just ordered the part to do our's. We had our liftmaster installed in 1998-2000, so the part should fit.

[@davidforadori5852]

great video!

[@michaelcasey9383]

Well? I did mine today and it went fine. It wasn't easy but wasn't hard either medium level diy for sure. Im 62 years old so anyone who is mobile can do this. In the process I was able to tweak every thing else. Greese chain, tighten loose bolts, ect....my door was off the ground about a 1/2" when I finished all that was necessary was to turn the down travel screw about a half turn. Rita and I can't thank you enough for this diy video, it saved us 100.00$ of dollars. Than you.

[@digitalcamproducer]

You’re welcome! So glad you guys were able to do the repair yourself! It’s nice when all you have to do is buy the part! Would be very expensive to call a repairman for this! Nice work!

[@jonm2416]

This will save me $200! Thanks bud!!

[@digitalcamproducer]

You’re welcome! Changing out the gear yourself will definitely save you a lot of money. And it’s not difficult to do! Thanks for watching!

[@jonm2416]

@@digitalcamproducer I did it yesterday with the part you linked to. It worked out great! Fun too! Thanks again😀

[@samuelparsons4521]

Nice video, thanks for the help

[@owentimo]

PERFECT!!! Thank you very much that was super easy! I bought the parts as you listed. I had to change the chain location in the drive sprocket a few times to get door would shut all the way. Since ot slippednpit of timing.

[@mytige20V]

Great tutorial. It will help when I finally get around to installing the gear assembly I bought a week ago. I have not done the install yet, I have been procrastinating. The third screw access is one royal PITA. Thanks for the video.. I have it dis-assembled and just need to put it back together. My problem was that the chain sprocket sheared off. But $17.89 from Amazon is a lot cheaper than a new garage door opener. It is also easier to replace. Thanks again for the video. A big 👍.

[@montebates9298]

Thank you so very much

[@user-cb1ym5lf4i]

Absolutely the best tutorial for replacing. Thank you so much !!!

[@digitalcamproducer]

You’re welcome! So glad my tutorial helped! Thanks for watching!

[@bacard100]

Why does the plastic gear keep going out please 😢

[@microwave_brother]

Thank you so much for this ❤

[@P.Jlive2024]

Took a little longer but I finally got it in... That's what she said

[@digitalcamproducer]

Haha! Thanks Michael Scott!

[@dannynguyen4857]

very good

[@squatchsquad960]

Helped a lot. Just a little more work for me as my opener was flush with the ceiling.

[@scottmoysh1160]

Thank you so much. This was very helpful

[@digitalcamproducer]

You’re welcome! Glad my video was helpful! Thanks for watching!

[@coreyr7013]

Absolutely the best tutorial for replacing. Easy to understand and follow.

[@KZ3W]

Thanks for the good explained video . 👍 ,, ✌️ . ( and the song at the end ,,, I was just listening to it ,, 😅 )

[@digitalcamproducer]

You’re welcome! So glad my video tutorial helped! Thanks for watching!

[@thomashuckaby8867]

Thank you!

[@harryhall7801]

this is a great video. i have the exact garage door opener. my top gear snaped off

[@SupaFragolata]

Thank you so much for this, you helped me from getting scammed $100 by a local handyman!

[@digitalcamproducer]

You’re welcome! Some of these home repairs can be done yourself easily! Just pay for the parts and that’s it! I always have to try before calling someone because I can save money fixing things myself if I can! Thanks for watching!

[@laurencepesek3812]

Excellent video, made me feel like I could make the repair and yes I was successfull. Thanks You so much!!

[@digitalcamproducer]

You’re welcome! So glad you were able to fix your garage door with my video! Nice work! Thanks for watching!

[@Green87]

Perfect tysm!! Also, if you’re door isn’t closing all the way there is a screw you can twist to adjust the travel so that the door closes all the way.

[@bacard100]

The best video anywhere! I did this 5 years ago and I’m doing it again!! Why does the plastic gear only last so long? Is there an issue with this model???

[@kayakterp]

Nice video, thanks for illustration. If I'm not mistaken, that's an old Cadillac I see in the video. I had a couple myself, GREAT CARS!

[@digitalcamproducer]

You’re welcome! Glad my video was helpful! And yeah that’s my dad’s 1977 Cadillac Coupe de Deville. Still drives it to this day!

[@ggarl12]

Thank you very much

[@digitalcamproducer]

You’re welcome! Glad my garage door opener repair video helped! Thanks for watching!

[@coxandrewj]

Superb

[@digitalcamproducer]

I’m glad my garage motor repair video was helpful!

[@emiliomonteromadrigal3897]

Excelente

[@wenbai2560]

Great tutorial! Have two questions: 1) I can hear motor running sound, but how to test and make yourself sure that motor is still working normally (i,e. wires not partially burned out)? 2) I saw you replaced the upright gear and sprocket. How to be sure the horizontal gear attached to the motor is good such that no need to replaced? Thanks!

[@pzajonc]

I really appreciate this video and the Amazon link. All was great, with one issue: in the video " the trolley was about an inch away from my vice grip" -- its about 6 inches for me though I could not see my vicegrip slipped. So close, yet so far. I will try to pull the chain feeding into the sprocket tighter so the outgoing part of the chain lengthens where I need it. The door stays open by 6 inches at this point. If anyone can give a comment I'd appreciate it! Happy Springtime!

[@pzajonc]

Ok here's my own reply -- video may be needs to state to tighten the chain from the fixed end when re-sprocketing it. That helped me with the last step. Everything else in this video completely matched my situation, including the difficulty accessing the 5/16" nuts holding down the worn out gear! Thanks

[@digitalcamproducer]

Hey I’m glad you got the trolley situation resolved! Yes I think you’re right. The location of the trolley can be adjusted when reattaching the chain to the sprocket. Lots of things on my mind when doing this repair and shooting video at the same time. But I’m glad you got the repair done! Thanks for watching!

[@dontrustwhiteyevery1]

Thank you my wife would not let me buy a new garage door so I have to fix this the same way you did yours÷!😁😁😁

[@digitalcamproducer]

Glad my video helped! At least you’re saving money! Thanks for watching!

[@Fedup10710]

I use a 5/16" ratchet wrench on the one hard to reach bolt. Kobolt makes one with a slightly longer handle. Couple of 1/2" open ended wrenches to loosen/tighten chain. Also lubricate the old plastic worm drive gear and top chain sprocket before installing new assembly.

[@digitalcamproducer]

Those are some good tips you added! I definitely would’ve used a ratchet on the hard to reach screw but luckily I found something at that house that worked without having to drive back home to get my tools! Thanks for watching!

[@barryp5334]

Great vid, but why did you not replace the main gear of the motor? It's in the kit. Just an observation but why go back in there again. The main gear off motor is just as old as parts that went out.

[@SeanKennedy009]

Low ceiling clearance above garage door opener. I’m able to loosen and disconnect the sprocket but unable to lift it out. Any suggestions on how to get out old sprocket w/o removing the whole unit?

[@jeremyb8941]

The one screw that’s so hard to get back in the gear kit .. I just run that screw down from the top.. saves time and frustration..

[@digitalcamproducer]

Oh yeah! That is a great idea for that tough to reach screw! I will remember that! Awesome tip! Thanks for watching!

[@PristineReviews]

Do the pins holding the gear the gear just slide out? Mine are stuck af

[@yaohkhanandaout3292]

I wish I saw this three days ago. I would have bought a new Chamberlain opener.🤦🏿‍♂️🤦🏿‍♂️🤦🏿‍♂️🤦🏿‍♂️🤦🏿‍♂️🤦🏿‍♂️🤷🏿‍♂️

[@karenplayford5133]

My chain was off the top gear so I loosed the tension and put the chain back on. Now it goes a few inches…. And goes tight and snaps back into place without allowing the chain to go further. The underside sprocket etc are engaging fine… could I be having the same problem as Gio Tor? Not sure exactly what is wrong please help! Thanks so much!

[@bw1498]

I replaced the part, but my chain only moves a foot or so then stops. What did I do wrong? The only difference is my top chain sprocket snapped off vs your inner gear wearing out. Same replacement part tho

[@jeffkaminsky7816]

What do you do if you replace the sprocket assembly with a new one and now the big white gear and the big worm gear are so tight that the motor can't spin?

[@garybrumm6395]

While you have everything accessed and right in front of you, why don't you check the other bushings for excessive play, wear and binding? It would be an opportune time to lubricate these other bushings even if they don't require replacement. Otherwise, great video. Well done!

[@montebates9298]

How do you know if the chain is to tight

[@paullancaster7066]

I've been a tight-wad and only purchased the big, white, nylon cogwheel. Does anyone know how to remove the black securing pins that hole it in place on the shaft please?

[@christinedeforge]

Because of my husband’s health issues I’ve started doing more DIY repairs around the house. Your video was great, thank you for that! I followed it step by step and it appears to be installed properly. However I haven’t tried it as the chain is seriously sagging. I clamped where the trolley was located, but originally the sprocket holding the chain sheered completely off, leaving the chain hanging. The door opened 1/2 way and quit when I discovered the issue. I had to disengage the door to open it in order to get the car outside. Before engaging the door, like you said, I want to test it. I don’t know if I moved something I shouldn’t have. Will it tighten up or do I need to call a professional?

[@christinedeforge]

Update: The line (connected to the chain) was off the pulley at the other end causing the huge sag (it must have been off for a while, causing the original problem); we got that put back on. Before putting on the chain, we hit the button to bring the motor to the down position (some thought to figure that out:) and brought the trolley all the way to the stop before the motor. After loosening the chain to allow it to be put around the sprocket, we tightened the chain so it was 1/2" above the bottom rail (a little sag) per other videos we watched, connected the door and seemed to have fixed the problem. A huge thank you for instructions on a repair done for less than $20! Yes, a lot of time was spent, but I learned and gained confidence. I'll never look at a garage door opener the same again!

[@ydiscovery3284]

hi, thanks for posting the video. I am in the middle of replacing the sprocket now but I am stuck. I followed all your steps, when inserted the new sprocket in the large gear hit the worm gear and was not able to put it all way down the housing. The worm gear is sticky due to the old gear shaving creased together on the surface of the worm gear but not a lot of them. I am not sure if I need to and how to replace the worm gear. HELP PLEASE! Thanks a bunch!

[@digitalcamproducer]

Sorry the worm gear is giving you trouble. The main sprocket should slide right next to it. Can you rotate the worm gear a bit? It’s probably locked in place. It might be a case of wiggling and rotating the sprocket/worm gear enough to allow it to slip in place. Hope you get it installed without too much trouble!

[@ydiscovery3284]

@digitalcamproducer thanks for your reply. I finally bought a genuine part and put it in without any issue. The problem was that the part I first got was aftermarket.

[@Chief_5]

Mine lasted 15 years of using it probably 4 times a day, changing it was easy, a little adjustment to the chain but fairly easy.

[@digitalcamproducer]

Yes the replacement of the sprocket on the garage motor is fairly easy to do. The chain adjustment is a little more daunting but not difficult. You definitely save money doing this yourself! Thanks for watching!

[@Chief_5]

@@digitalcamproducer actually have a Marvin Allen salesman come to quote me new systems, he didn’t mention that I might be able to fix it myself.

[@tablespoon888]

Anyone know where I can get these parts these day? I think the manufacturer stopped making them.

[@Fedup10710]

e-bay

[@digitalcamproducer]

Thanks for your question! I listed the parts in the description of the video. They’re available on Amazon. That’s where I got mine! Hope this helps!

[@hydroguy8]

@@digitalcamproducer same 1 week ago

[@daniellazo6527]

What can you do if your trolly got moved after you removed the chain and you don’t have a reference of where it was before

[@KZ3W]

Hey There . I think I was reading ,,, you might have to then adjust the UP and DOWN force settings . ( Also KZbin videos on this ) . But as even a better maintenance step ,, I'd check the rolling and balance of the door ,,, the proceed with the UP / DOWN force adjustments . I always ( and read ) it's best to have a good manual opening door to put less stress on the motor / mechanical parts . Hope this helped a bit .

[@digitalcamproducer]

You can also detach the chain from the sprocket on the top of the garage door opener. Then adjust chain until the connector is as close to the trolley as possible… then reattach the chain to the sprocket. Then as the other commenter said, you can adjust the up/down limit switch on the opener. Only if necessary. Hope this helps!

[@joeboyd7721]

Good job and very helpful, but don't ever use pliers on nuts and bolts. I hope your excuse is you forgot those also. You should have said that. It would have made you look better.

[@digitalcamproducer]

Thanks for the advice! You’re right it’s not good to use pliers in nuts and bolts. Those were the only tools I had on me when I was doing the repair.

[@blaketankersley2449]

Good video but broo you have to pronounce the letter T

[@billhamilton7524]

Great video thanks ,,but you didn't use all the new parts ,,seems you only needed the one gear