08 yz450f water pump

[jasangshaf]

How do you remove the impeller and shaft assembly? I have removed the cover to and I turned the impeller a few times but it did not loosen up.

[grayracer513]

Remove the right side crankcase cover (drain the oil first). You'll find a pair of flats ground on the inboard end of the impeller shaft that will let you use a 13mm wrench to hold the shaft while you unscrew the impeller.

Trying to do this by unscrewing the impeller from the outside runs the risk of breaking the drive tab off of the shaft, and will prevent you from inspecting the shaft for a groove worn by the seal.