After pulling power to the air handler discharge the run capacitor for the blower motor. Just use and insulated screwdriver and touch both terminals WHILE HOLDING INSULATED HANDLE.
TAKE PICS OF EVERYTHING. I still do this on wiring setups to this day
Note wiring setup you can draw it out or even leave them attached for now.
Open the case with a hex driver probably a 5/16ths bit.
You will see a squirl cage motor with the blower motor in it.
You remove the whole squirl cage assembly. Its not hard just a few screws holding it in and then the whole assembly slides out.
remove mounting bracket from squirl cage and remove set screw from motor shaft and get the old motor out. this can be a PITAzz if it has been in there for eternity and there is a killer tool for it called 'the ultimate fan puller' or something. you can get it out too with some work usually and maybe some oil.
replace, remount and get set screw on FLAT side of new motor shaft. it cannnot slip.
rewire and run with a hand on the disconnect to make sure it spins nice and easy.
oh yea your new motor may have three or so speeds (lo, med, hi) so you will have some excess wires (2)at the end. this is normal.
you are sure it is the motor right, not a run capacitor or fan relay? just an expensive part and PITA if you dont have to .
take care and good luck
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