ok had a talk to an otis guy. what is the reason you are removing/replacing the worm gear? is it bc of the backlash? if so the back lash is adjusted via the thrust bearing end. most of the time the tab washer has broken. is the worm gear at the thrust end threaded. if so to adjust the backlash you have to -
-remove thrust cover
-there is a screw to adjust the worm(is about 1 to 1.5 inch wide), sort of with a half screw head that i think has a tool for it but you can use a flat screw driver to adjust the worm in and out.
-when you have moved the screw to the desired point flip th tab into place to lock the screw down.
- now you generally do this with the counterweight landed and everything still attached.
not saying this is for every machine but it most likely the same.
now when removing the worm you disconnect the collar on the brake drum, remove the thrust cover, with a bin lid underneath to collect the oil, the whole worm should come out the rear end with the crown wheel removed. you may need to undo the ring nut assembly on the thrust end , not sure.
not sure why your replacing the worm but try this and let me know.
cheers mate.
