Track yoke
First you need a torch, then a 14-20 lb. sledge, I like a 20. If the machine has a quick link and you just remove the four pad bolts and pad that's great. Most will have a master pin that will have a dot or dimple, hopefully the pin was driven in from the inside rail. You will need a large drift to use to drive the master pin out ( if you have a rental place close by pick up a jackhammer bit and cut the point off) make sure it fits close to the pin size. Move the master to the sprocket or idler end, I use the idler most of the time with a 8x8 or 12 x12 block in front of it. Loosen the track adjuster fitting to let the grease out and push against the block to move the cylinder back. Let off the block just a little. Heat the bosses on the rail inside and outside where the pin goes threw but try not to heat the pin cherry red. You are trying to expand the bosses so the master can be driven out. Most masters are just a little bigger on one end or have a little taper, this is why it helps if its driven from the inside out on the install. You want a good hit on the pin, can't play with it, you can swell it if it gets to hot (pin) and really cause a lot of harder work driving it out. Internal wear on the pin can also cause it to drop in the bushing and make driving it out hard. Once pin is out be careful of you garage door, if the track unwinds off the sprocket and you are close to the door the track may cause some damage if it rests against it. Unbolt your yoke and remove the idler shims as needed and slide the idler off unto the track rail. I have two different jackhammer bits with a wobble hose and handle to take the shock out when hitting it along with some RR pin drivers. A rose bud on the torch helps to get a quick heat to the bosses. Wear your PPE, safety glasses, gloves, and thick coveralls. I have metal in both legs from master pins/ drivers flaking apart over the years. It would be nice if you had someone close by with a portable pin pusher, to make the job a little safer. If you haven't done it install the safety bar/lock on the loader also. And do not try to catch or pick up the pin once it comes out, had a customer try to do that several years ago and had to carry him to the ER after I told him to leave it alone. Most will install a new or re man idler due to time and cost of parts like bob said also. It sounds like a lot of work and it is, even after several hundred you have those that will fall apart and those that make you wish you were doing something else.
