Vibration intermittent

[Pam Pryor]

Just looked at a Beneteau 285. 10 yrs old. Volvo 18 hp Diesel. Gori 15 12 prop. Low revs ok, and at Dock no vibration. Open water at 2500 started to vibrate. Backed it down put it in neutral. Reverse, high rev. then Neutral. Up to 2500 fwd, now no problem. Appears now to run great. Should this cause concern or is it possible there was something fowling the prop? Thanks

 

[Terry]

Hi Pam, it could have been something fouling

the prop. Many factors involved. Vibration can come from the transmission on through to the prop. Zincs tend to rattle if they work loose. I'm assuming you're looking at buying it, in which case you'll want to haul it for a surveyor's inspection. Let the surveyor know and they can look for causes. If the boat has been sitting in the water and not cleaned in awhile the prop and shaft can collect marine life, which can also cause a vibration.Terry

 

[Pam Pryor]

Survey inconclusive..

Thanks Terry...Survey couldn't find anything. There was no Zinc on the shaft when hauled and the boat had no signs of debris on prop or shaft. Possibly the zinc worked loose and off when put into reverse? We'll find out in the Spring!!Thanks

 

[Terry]

Hi Pam, so you bought the boat?

Kingston, WA? If you happen to see an H28 named "Our Quest" in your area, that's our old boat.TerryS/V Belle-Vie

 

[Kevin]

Could be many things

Hello Pam,Fouling could be but I would think that the likely hood of the propeller going through a momentary cavitation is greater. The enviorment that the vessel was moving through could have caused the propeller to cavitate and once the propeller was slowed and restarted again the propeller filled with water again reducing or eliminating the noise. Hope it helps. Sorry for my delay I was out for the hollidays. Kevin