noise at 1000 to 1500 rpms

[JJB]

I have a 200 175vxss 25 " on a 20' bayliner that when I run it at low rpms I hear a low grumbling Noise and vibrations from 1000rpms to about 1500 rps then goes away . I have great hole shot and good top end speed with it and no odd noises . but when I return back down to 1000 to 1500 I get the vibs and grumbling noise . The engine sound better at those rpms in neutral but still has some vibs . any ideas what it may be ? I am running a 4 blade ss prop 18 pitch and get about 5200 wot . Thanks for the input !

 

[kynolan2183]

Re: noise at 1000 to 1500 rpms

First step: Remove the prop, if possible, and put on muffs to see if the Vib is from the prop.


Let us know what happens.

Kyle

 

[Gary H NC]

Re: noise at 1000 to 1500 rpms

Try another prop and see if it still does it under load.On the muffs may not prove anything.

 

[JJB]

Re: noise at 1000 to 1500 rpms

Hey thanks for the input , I think I order a prop from I boats this week and let you know how I make out

 

[Dhadley]

Re: noise at 1000 to 1500 rpms

Take the prop off and look inside the gearcase. You'll see a bolt at 12 o'clock and 6 o'clock. See if either, or both, are loose.