3.0L Vibration at 2500 RPM

[trevtt600]

Hello All. Took the boat for a ride with "new" motor today. Its a 3.0L mercruiser. Have an alpha 1 drive. At 2500 rpm when coming off the throttle i get a pretty serious vibration. It you try to cruise at 2500 same viration only not as bad. Seems like it is happening when the drive gets unloaded from slowing down. Just had the engine aligned, and the mechanic said the coupler is alittle worn, but should not cause any issues. Should i check or replace the u-joints? Any ideas i can check into?

 

[JaseBosto]

Re: 3.0L Vibration at 2500 RPM

Any issues with the prop? dings? Make sure everything is good on your motor, such as it firing on all 4 consistantly just to rule that out I suppose....

I had a vibration with my 2000 3.0 mercruiser alpha 1 gen 2 and it turned out to be a small ding with a burr on the prop. My vibration didn't show up till WOT but... You would be surprised how much of a difference a small ding on the prop CAN make...

 

[trevtt600]

Re: 3.0L Vibration at 2500 RPM

If it helps, when you rev the motor out of the water a little above 1500 rpm, it makes the same vibration/noise.