Stairmaster 8G Gauntlet Service Manual page 28

3. Use a 1/8" allen key to loosen the gear
box sprocket set screws
4. Push the idler arm up to release ten-
sion on the chain, walk the chain off
of the idler sprocket, then
pull the chain and gear box sprocket
off of the gear box shaft.
NOTE: Take care not to lose the key
that may drop from the gear box
shaft.
5. Before removing the gear box/alter-
nator assembly, the brake and speed
sensor must be unplugged from the
lower control board.
Page 28