This article concerns specifically the users of boats that do not have a thrust bearing in their boat. This is to say, when the thrust of the propeller “pushes” the engine through the anti vibration mounts. In this case the marine engine mounts have to push the boat and resist the thrust forces of the boat.

The engine mount has to be prepared to be able to withstand the forces of the thrust in combination with the forces exerted by the waves/currents.

When cruising on the boat, safety is first and so it must be always. One of the matters that is always forgotten is the levelling of the engine with the height adjusters.

If the engine is highly levelled the height adjusters have to withdstand cyclic bending moments that can damage the studs by fatigue. A visual example is shown below.

All height adjusters when submitted to bending moments offer a decreasing resistance as shown on the below video.

Damage of the stud by fatigue
Some of the areas that had a margin for improvement was the installation of the mounts. They were not placed fully on the engine bed. The mounts looked also to have much deflection.
Broken engine mount height adjuster.
The installation had too much levelling to our taste, around 12mm. This is something that can be very polemic. But to our point of view the lower the levelling the better.

If additional levelling is required, shims or shockfast can be used beneath the engine mount just like shown on the picture below.


Ellebogen highly recommends not to level the marine engine mount more than 3 mm.




This safety factor is highly recommended, no matter if the engines are the 2YM15, 3YM20, 3YM30, 2GM20, 2GM20F, 3GM30, 3GM30F, 3JH2BE, 3JH2TBE, 3JH2TE, 4JH2BE , 4JH2TBE, 4JH2HTE, 4JH2DTE, 4JH2UTBE or 4JH2UTE.

Do not hesitate to contact Ellebogen if you have questions. You can easily contact us by clicking on this link.