Customer Reviews

41C4220A Sears Craftsman Liftmaster Gear & Sprocket Assembly Kit

5 star:		(213)
4 star:		(50)
3 star:		(4)
2 star:		(3)
1 star:		(4)

 

 

First, I wanted to offer compliments to other reviewers that described the symptoms of the gears being bad - the "snow", the stop-and-starts, the stop working altogether but can still hear the motor running - nailed it exactly. Very clear to me after reading those that this was exactly the product I needed. It is exactly what it says it is - an OEM Liftmaster gear replacement assembly. The directions that come with it are excellent - step-by-step, and it explains exactly what you need to do. The directions are the best part of this product - if they were not so well done, it would be impossible.

No knock against the product, but installation was considerably more work than I expected. I had visions of undoing a couple of screws, popping out a gear, putting in the new ones, and being done - boy, I couldn't have been more wrong. The process can best be summarized as "take your garage door opener completely apart, removing all pieces, wires, etc. Around 30 to 50 screws, wires and pieces to remove. Replace gears. Re-assemble." Very important to ziplock and label all pieces and screws as you go, label the disconnected wires with masking tape so you keep everything straight.

With practically no re-work or mess-ups, it took me every bit of 4 hours for the fix. Was starting to wonder if this was the best way to spend my Saturday afternoon or if I just should have bought a whole new opener.....of course, would have had to install that too. That said though, the product works exactly as promised, and the directions are great.

Also kudos to Amazon seller "Sanford and Son" - I ordered it Monday night, was in in mailbox on Friday, in time for the weekend project.

I benefited greatly from comments others made about this product and how to install it, and I thought I'd add mine for any who are looking at getting this. My 11-year-old Liftmaster chain drive garage door opener stopped working and had the same worn out sprocket that so many have described, with the white snow shavings, etc. I too feared I'd have to spend $100s getting it fixed, then I found this great product on Amazon. I installed it last night, the whole process, including finding tools and adjusting the chain and door afterward, took me about 2.5 hours, but the actual removal and installation of the part took only about an hour. Garage door works great now, and is quieter than before.

For the installation, I did what the reviewer before me did, which means I didn't remove all of the stuff the instructions said to remove. Here's a fairly detailed step-by-step of what I did -- my inner and outer "trolleys" (the things that slide the door along the rail and that have the red release handle) were already connected in a good position with the door closed, so I didn't have to adjust anything there: (1) unplug the unit and loosen chain following directions -- I suggest loosening as much as you can -- I didn't at first and had to loosen more to get chain off, which added time to the overall project; (2) remove chain from top of opener unit and attach it to rail so it doesn't fall -- I did this with a plastic tie thing; (3) remove three-sided housing from opener (total of 8 screws hold it in place); (4) unscrew back side of housing (2 screws at top corners), the one that has the circuit board, and let it just hang there (I didn't remove the front side of the housing); (5) remove the white plastic clip and little gear/sprocket from the bottom of the old spindle -- the plastic clip came off by just pulling the front prongs apart a little and pushing it out and the little gear piece just comes down and off; (6) drop the door travel sensor/adjuster thing by squeezing the top of the plastic bracket that holds it where the bracket hooks into the metal plate above it, and let it hang (not sure this needed to be done, but I did it); (7) remove the 3 screws holding the spindle assembly in place at the top of the unit -- this was the "toughest" part and, in part I think because I didn't remove the motor or other parts per the instructions, it was a little tricky getting to the three screws, especially the one nearest the circuit board and a little obstructed by a small bundle of wires, but with patience and care and the right tools it can be done -- I used a small ratchet wrench with an extension (extension was needed for two of the screws) I think the socket I used was 5/16"; (8) remove the old spindle through the top; (9) the screw holes in the new part are not threaded, as others noted, so I threaded them by putting a screw starter (an awl-like device that I think is designed for wood) into the screw holes in the new part and turning it as much as I could and then driving the screws part way into the holes and then taking them out -- all of this with the new part on the floor of the garage; (10)clean the mound of white plastic shavings off as best I could from the metal "shelf" above which the white plastic "screw" is located (like others, I didn't need to replace the plastic screw); (11) remove the white plastic clip and small gear from the bottom of the new part (not sure this was necessary, but I did it); (12) drop the new part in place from the top and screw it in place, being careful to align the square holes for the plastic sprocket cap on top of the unit, front and back, if you want to be able to use that cap -- screwing the new part in place in the tight space with the motor in place was again a bit tough, but doable with patience and care; (13) replace the small plastic clip and gear at the bottom of the spindle; (14) snap the door travel sensor/adjuster bracket back into place in the metal shelf above it; (15) use the supplied lubricant and an old toothbrush to lube up the new sprocket, the old screw and the gear at the bottom of the spindle; (16) plug the unit back in and run it briefly without chain attached to make sure it works; (17) reattach chain and run the unit to see if adjustments need to be made on the door's "travel" -- mine needed a lot of adjustment because it was going down too far on the close and not coming up far enough on the open -- I also put some oil on the chain, the sprockets on either end of the chain and on the rail before running the unit with the chain attached; (18) put the sides back on the unit.

Sounds like a lot, but it's very doable with patience and care, especially in removing the screws to get the old part out, starting threads for the screws in the new part (with the part on the floor), and screwing the new part back in. My socket wrench slipped a couple of times while removing the old part and putting in the new part, but, fortunately, I didn't hit or break any vital part. The only tools I used were a flat head screwdriver, a socket wrench with extension and one socket (5/16", I think), a screwstarter awl-like tool to thread the screw holes in the new part, an adjustable wrench to loosen the chain tension, an old toothbrush to spread the lubricant, a plastic tie thing to secure the chain to the rail, and a small flashlight (the kind you wear on your head) to help me see what I was doing (it was night time and the garage door was shut anyway). Oh, and a ladder. Be careful on the ladder!

Certain Liftmaster garage door openers have a plastic gear that is prone to fail after a few years. I had one of those, the 1155. The symptom? You press the button, you can hear the motor running but the chain (connected to the door) doesn't move. When you take the cover off the garage door opener, you can see that it's stripped and white plastic shavings are everywhere.

I asked the local garage door repair company how much they'd charge to replace the gears. About $200. They even wanted $56 for this gear and sprocket set alone. So I ordered it from Sanford and Son for about $30 (which includes shipping). It arrived quickly with a set of well-written and well-illustrated instructions. (There's even a list to check off as you complete each step.)

I'm about average in handyman skills. As I removed each part, I put it on a piece of paper on the floor and labeled it so I'd remember what it was when I had to reassemble it. I followed the instructions exactly, removing the cover, then the motor assembly and then the sprocket and gear set. It truly was easy and took a total time of about 2 hours. It's important to replace the worm gear (Liftmaster's advice) and to apply lots of grease to the gear when you install it.

Now the garage door opener works perfectly, and I got a lot of satisfaction out of repairing it myself. Thanks to Sanford and Son for the excellent kit.

Length:: 6:33 Mins

Arrgh! Why didn't they tap the mounting holes?

This is an inexpensive way to keep your garage door openers running when its drive gear and sprocket wear out. If you know where all your tools are and how to use them, you really can do this repair in about an hour, with one hand, while filming with the other hand. If you have a helper more time will be required.

The kit includes the drive gear mounted on a shaft, mounting flange, limit switch gear and retainer, grease, roll pin, and some assorted bushings and washers that I did not use. The instructions are clear and concise. Hopefully the video will make your work even easier.

This assembly is used in many garage door openers made by Chamberlain and sold under several different names including Liftmaster and Sears Craftsman.

Tools needed - you don't need much:

* 1/4 in socket wrench or flat blade screwdriver to remove the housing cover
* 5/16 in socket wrench with 6 in extension or combination wrench for the sprocket mounting screws
* two 1/2 in wrenches (or one 1/2" wrench plus a crescent wrench or vice-grip) to loosen the drive chain locknuts
* Glass tape, duct tape, or plastic ties for temporarily securing the chain to the rail
* Stepladder. You will need to reposition it frequently so two ladders are better.
* 10-32 tap ***IF*** your kit arrives with untapped holes like mine did

Note that I did not replace the worm gear. As a rule, if a gear is worn to the point it requires replacement, any gear in mesh with it should be replaced too. However, the worm gear didn't appear to have any wear and if it wears out I guess I'll just have to spend another twenty bucks. The garage door opener in the video has been working for over ten years and it's the most frequently used. If this repair lasts me ten years I'll be happy.

Five stars less one for having to tap holes that should have been tapped.

I found a very quick and painless way to replace my worn-out sprocket wheel. Since the worm gear was in great condition, why bother with replacing it. To remove the sprocket, follow the directions on relieving tension on the chain and removing it. Remove metal enclosure by removing a few screws. Next remove the screws that secure the circuit board (the side opposite the side with the light) and just let it hang there by the wires. This simple action allows you to access the 3 screws that hold the sprocket assembly in place. Now remove the small lower plastic gear and plastic cotter-pin at the end of the sprocket shaft (see instructions). Finally, use a socket wrench and remove the 3 screws that secure the metal spocket assembly to the top of the garage door opener. Simply lift out sprocket assembly, and insert new one, reversing the order of disassembly above to assemble. Grease the wheel. Attach circuit board and put enclosure back on. Done!

This kit is well put together and even included a few extra washers and clips that I did not need to replace. I have basic repair/tool skills and enjoy taking things apart, so the replacement was easy and only took me less than an hour. If you are not so inclined or unsure, here are the basic steps: unplug the opener, unscrew and take off the opener covers, unhook a few electrical connections and circuit board connectors, remove the motor, remove the worm gear by unscrewing the set screws and sliding the washers off the drive axle, replace worm gear and parts, remove the drive gear assembly from the opener chassis and punch out the drive gear pin, replace drive gear and pin, grease gear and replace drive gear and assembly, replace motor, reconnect everything. The next one will go much quicker now that I've done it-

When your springs get weak it puts added strain on the opener. That causes this sprocket bearing to wear quickly. You will notice the chain becomes loose. This is a fairly easy kit to install. It requires basic tools and some patients, also a long handle 5/16" nut driver would help. It took me just over 1 hour. Don't rush, follow the instructions and you'll be fine. Remember to use the grease that comes with the kit to lube all the moving parts.

I bought this kit and installed it. Just some time on a ladder. Carefully removing, cleaning, and installing.
Two things that could have been better in the instructions.
Yes, it says after removing the chain, move the trolley back to the locked position - Yes, I was a dummy and didn't do it - It's important!! Second, the round upper bearing block and shaft support that screws onto the top of the unit has ONLY one hole for the chain guide attach screw to go through. There are three positions that this upper bearing plate can be attached in (but because the product only has one hole for the screw) there is only one of the three positions that allows it to be assembled properly. I was too tired to disassemble and re-do it, so the chain guide is now held in place with only one screw.
Watch for these things and you are home free.
Wife now thinks I am a mechanical genius.

When my garage door went down and wouldn't come up again, my friend advised me to check and see if the gear was stripped. It sure was. Then he pointed out that I could buy the parts to fix it on Amazon, so I did. I'm not much of a handyman, but the parts fit perfectly, and the instructions that came with the kit were easy to follow. Now my garage door actually runs more smoothly than it did before. I would recommend this kit to anyone.

This is an excellent and economic kit. Pretty much anything that wears in these garage door units besides the motor is supplied for replacement. My one gripe with it is that the directions could have been better, as the unit has to be stripped down quite a bit. If you're wondering how much, unplug the unit, take off the outer panels until you can see the gears and all the "snow" that everyone is talking about. The additional parts that get replaced with this item (vs. just buying the gear) are mostly on the motor, which has to be removed bracket and all. The center shaft with the broken gear has to come out through the top of the housing. On mine there was 6" of clearance between the top of the opener and the ceiling which allowed me to remove it. If you have less room than 6" it is possible the whole opener will have to come down. While the directions are adequate, they do require caution and studying in order make sense of what needs to be done. There are basically no re-installation instructions, so you have to reverse the disassembly directions.


This kit repairs four different styles of door openers. The only difference is in the way the bearing assembly is held to the motor. Two of the styles are held together by retaining rings, while the other two use a collar/roll pin design. Under tools needed the instructions mention a 5/32 punch, but this is not needed for the retaining ring designs. I used a pair of snap-ring pliers to remove the retaining ring that was on my unit. It wasn't super stiff, so you could probably get away with regular pliers. Either way, the necessary tool is not mentioned in the instructions. On that same note, there is one press-fit bushing that is supplied that is never mentioned anywhere in the directions. This bushing goes in the motor mount plate and is the one that holds the bottom of the shaft that the offending gear rides on. I changed mine, but I also had a 20 ton hydraulic press at my disposal. Changing this item is not essential by any means, but I wouldn't attempt it without a proper press. I imagine that's why they left the part completely off the instructions.

The door works like a champ now. It seems a lot quieter than it used to be. I don't know if it was just that much louder with the damaged gear or of all the supplied grease that I lathered on the parts made the difference. The job is not very difficult for someone used to repairing things, however I could do it again in less than half the time simply because the directions wouldn't have me scratching my head.