Offshoreonly.com - B1 Via 454 MPI Vibration

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Quote:

Originally Posted by BUP (Post 4600555)

to ask from post number 1 - You posted the vibration starts at 3500 rpm and above. So you have no vibration from 650 rpm thru 3450 rpm ???

Yes zero vibration below the 3400 rpm mark. While on the boat last week for attempted impeller change I did notice the vertical motor mount bolt (into stringers) washers loose. That will be my first adjustment then hit the water again and see what tightening nets vibration-wise.

Thanks for everyone's input to date, very helpful and gives me a lot of points to check.

I guess I have my answer. SB engine 3 of the 4 vertical forward mount bolts will not tighten, just spin. Port 1 of the 4.

Keith