[willy]

need some ideas from you guys before I head back down to my V.
Took my son down yesterday to install rod holders on boat, went well and we decided to go out and do a little fishing late in the day.
Motor is running like a champ, full rpm and speed but a noise is occurring at higher rpm that sounds like a metalic vibration, medium high pitch and would come in only under load when you were first accelarating then quiet down and sometimes disapear.
Stopped motor on the watetr and pulled the cover, sounded like something was loose like a ball bearing in a paint can mixer machine but could not see anything wrong or loose. No alarms, no overheating, oil in reservoir.
Ran boat for another two hours and ran beautiful but noise would appear at certain rpms and repeat the cycle. Lifted the lower unit out of the water all looked tight there with prop but the noise seemed higher like around the base of engine block area but could not pinpoint at all.
Back at the dock had engine running with cover off and revving up high but could not get it to do it, only way was at speed on the water.
At higher rpm at high rpm at dock sounds like a two stroke swiss watch.

Oh and its a 1992 150 yammie.
Any ideas of what to look for let me know please cause I am stumped and now a little worried.
Only thing done diffrent on engine was I used Pennzoils new two stroke oil in the tank when I filled it up last time, I was going to use the yammie lube but it looked like he had been running Penn in it as it was not blue like yammie but black.