My 35 GTR has more vibration that what I think is normal. The motor has 116 hrs on it and I purchased it in Feb. I thought that the vibration was maybe just typical for the GTR since I had not owned one before. My buddy got in the boat a couple weeks ago and also noticed the vibration and thought it was excessive. The aluminum black death mikuni cover cracked across the top and bolts keep backing out of the muffler. The motor only vibrates when in gear and is worse at a low rpm. I have greased the prop shaft every 10 hrs and just bought a new prop for it last week (thinking my prop was not balanced). The new prop did not fix the vibration. When I turn the prop by hand (motor off) I can feel a "spongy" spot once per rotation. Checked prop nut and it is tight. Not sure what the problem is. Thinking something with the prop shaft. Any ideas? I'm in Central Florida and there are no Gatortail service centers around.

If you're breaking stuff from vibration, you've got a serious issue. I'd at least pull the prop shaft and check it out.

What about belt tension?

my twin thumbs and today's cellular technology

Most common causes for this are clutch rotor, belt, or prop. Probably clutch Rotor. More than likely not the prop shaft. And you already changed the prop. Pull the reverse cover and fire the engine up and watch the gap between the rotor and clutch disc if its not running true you will be able to see it. If it looks true put the motor in gear and rev it to 3,000 and watch the belt work. Also put it in gear and watch the prop spin and the end of the prop shaft. You should be able to see that also. I bet it's the clutch rotor though. You won't really notice it a whole bunch but the high frequency vibration it causes will vibrate everything to shit. Good luck.

Have u checked w millers in Ocala? Not sure if they work on them or not.

Florida mud motor in Melbourne is a gator-tail dealer.

This guy. You've got the stationary electric part of the clutch, then this guy that's keyed and turns with the crankshaft, then the clutch disc with pulley attached. If this rotor or basket or whatever you wanna call it is out of balance or unevenly worn, it will cause vibration.

Clutch rotor was the issue. Hoyt, from GT, sent me a new one. He said they had a bad batch of them a while back. Got it in two days and got her fixed. Running good now. Thanks for the help guys.

May be my problem also. Thanks for the update.