Have an 150XR6 2000 0t149393
It has a slight whine sound, similar to a gear sound. I don't believe it is the lower unit. I still hear the sound idling in neutral.
I do not here the sound while on pad, but likely cant here it because the engine drowns the sound out at higher RPMS. The pitch of the sound does increase as RPM goes up.
Interestingly, I do not seem to notice it when first started for the day.
My first thought that possibly oil pump gear. It does have the metal gear, but I have heard the crank gear is still plastic.
I already have an oil pump delete kit, but prefer to keep it oil injected (more convenient).
I don't recall hearing this sound in the past.
Thoughts, other things to check!
Thanks in advance!