Replacing a Garage Door Gear - Lift Master - Part 2

I shared yesterday how I took out the old gear. Today, I am sharing how to put the new gear in. 


If you remember, you had to take the pin off the bottom of the gear to get the little white gear off. Take off the clip on the new gear and then remove the little white gear so that the gear will fit down into the spot. 

You can see in the picture  that you need to go in at an angle to get the gear through the hole in the top of the opener. Once you angle it and get the plastic gears through the hole, you can slide the shaft through the hole below which will leave the metal gear at the top and the larger round metal piece that screws the gear into the opener. 


The metal piece spins around freely so you can line up the holes where the screws go in. 

Once you have the holes lined up, replace the three screws you took out to get the openers gear shaft out. 

Once you screw the three metal screws back in and the metal on the top is secure, you need to put the small plastic gear back onto the bottom of the shaft. Hold that on while you put the plastic fastener through the holes and make sure it snaps into place. 
 
Next you need to put the chain onto the metal gear on top of the opener. Make sure the screws are tight so the gears don't wiggle which would lead to breakdown of the gears. 

Remember I shared that you should wear gloves as I have black on my hands days later even. I put gloves on half way through but I remember when Jay put the door in, he wore gloves. I should have remembered that but it has been years and I forgot about that until I had black hands. 

The chain will be hanging and loose but it takes a bit of pull even with the loose chain to get the chain lined up and on the gear right. 

Remember the opener is still unplugged. Put the chain onto the metal gear at the top of the opener. Try to make it even on both sides so you don't have to adjust the opener much after you have it put back together. 
 
I stood behind the opener and tried to line up the chain evenly on both sides and then slipped it onto the gear. I had pliers there from when I tried to get the chain on before loosening it. That was all explained in the last post. I didn't use the pliers for anything in the end.  


You can see how the chain is hanging down even after I get it on the gear. I then tightened the chain up by moving the back nut on the "open" side up to the nut on the front side. You shouldn't have to move the nut on the "unopened" side at all. I messed up and had to fix it later but that is why I am sharing it with you so that you don't have that problem. 


The instructions say to tighten the chain so that it sits 1/4 to 1/2 inch above the base of the metal chain guide. If you tighten the back nut all the way and the chain is touching the metal bar, you may need to move the front nut just a bit and then tighten the back up so that the chain is tight and both nuts are tight as well. 


You can see the worm assemble which is the sideways white gear and the gear we replaced is behind that and they mesh.

Tomorrow, I will share with you how to adjust the door once you have the gear in and the chain on. Remember this is for the LiftMaster and Craftsman door openers. Most chain gear assemblies are similar. This is just my opinion and I am not a professional but I can share what I learned.