Knock when tilting motor

[caritobito]

Hello. Ok this just started on my 01 Yamaha 90Z. Not sure what it is. If the boat is parked, or in the water and not moving or gowing slow and I trim the motor up or down it works fine.

However when I am actually going say at least 1/3 throttle, and I trim the motor up or down, I sometimes get this loud clank noise from back there. I dont know how to explain it, but I can hear it and feel it. If it does this and I bring the boat to a stop (even if I leave it in gear) and use either the trim button on motor or console, I can never duplicate it.

It seems to only do it when moving and only when tiliting and then not every time.

Any suggestions on where to start. I swear it seems to always be something.

Thanks

[robert graham]

Maybe try a little grease on the tips of your trim rams...they could be dry and sticking some?

[caritobito]

Thanks. I can try that. So just on the external part of the two metal rams that hydraulically move? Just seems odd that it only does it when I'm moving.

[robert graham]

Thanks. I can try that. So just on the external part of the two metal rams that hydraulically move? Just seems odd that it only does it when I'm moving.

When you're moving, the motor is pressing hard on those ram tips, and if they're dry they could be causing a "grunching" sound as the metal surfaces slide against each other. When you're not moving, very little pressure there. There's 2 small, square stainless steel plates that the tips contact...check them also. I'd check that big tilt ram pin that runs perpendicular to the tilt ram, for play, tightness, lubrication.