Yanmar sd50 repaired but whistling

[dan swift]

Hello all,
I am new and think I asked you this question in the wrong forum, sorry if you get this twice.
We lapped in a clutch on a sd50. All went well until we put it in gear. It went into gear fine but had a whistling sound? Again only when in gear, forward and reverse same sound. Does anyone have any ideas what we might have done wrong and could running this cause any lasting problems?
Thanks

[motion30]

Its happy?