1

I have a new 2.5 hp Mercury outboard motor on a used 12-foot aluminum boat. When I use the motor, it vibrates the boat and everything in it, which makes a lot of noise.

I'm doing what I can to eliminate rattles inside the boat:

  • Tightening loose aluminum boat parts, applying caulking to trim, etc.
  • Securing loose items in the boat, such as the oarlock horns.

But I want to limit the vibrations that get transferred from the motor to the boat in the first place.

What can I do to reduce the vibrations? The motor is brand new, so it shouldn't have any mechanical issues causing extra vibrations.

Photos:

enter image description here

enter image description here

enter image description here

enter image description here

Improve this question
3
  • It looks as though the back portion has a rubber pad sandwiched between the boat and another sheet of aluminum ... is that an accurate assessment?
    – Pᴀᴜʟsᴛᴇʀ2 ♦
    Commented Jul 17, 2023 at 20:29
  • @Pᴀᴜʟsᴛᴇʀ2 Good question. It looks to me like the black stuff is rubbery caulking wrapping a solid inner core, such as wood, plastic, etc. Maybe the purpose of the solid core is to make the transom thicker and stronger for mounting the motor, not reducing vibration. I'm reluctant to peel away the caulking to investigate since that would compromise the seal. I've sent a message to the previous owner to ask what he did there. Hoping to get a reply.
    – User1974
    Commented Jul 18, 2023 at 0:10
  • @Pᴀᴜʟsᴛᴇʀ2 It looks like it's plywood: i.sstatic.net/u11Wi.png
    – User1974
    Commented Jul 18, 2023 at 0:53

2 Answers 2

Reset to default
1

I used a portion of a mud guard to pad the motor from the boat. And I used plastic caps from juice containers to spread out the force from the clamps so that the clamps don't damage the rubber.

enter image description here

enter image description here

The installation went smoothly. But to be honest, it's hard to tell if it's reduced the vibration much.

Improve this answer
1

A contact at a marine supply company said:

One thing you might try is raising that motor up off the transom maybe by ½” if possible. We have found that the bracket actually sitting on the transom produces noise.

Improve this answer

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .