90HP Nissan outboard power trim...

Question

When I try to trim my engine up, the engine moves very slowly, then it catches and comes right up. I have never changed the fluid on this and would like to see if that helps, but I don't know how to do it as the only thing marked on the unit is the s***w that will make it manual lift or power lift! Help please!

Answer 1

always been like that?

sounds like it's acting normally.

you have 2 modes of operation:  trim and tilt.

when the motor is down in running position, it's moved by the trim rams.  They move slowly, so you can make minor adjustments while underway.  You should take off with the motor trimmed fully in, to keep the bow down and apply more thrust to climbing up onto the bow wave.  As you gain momentum and come up out of the hole, the bow will drop...then you start trimming up a little at time, giving the boat time to respond, until trimming out makes RPM's drop instead of rise.  That gets more of the hull and the motor out of the water, less drag means more speed.

When the trim rams are fully extended, the tilt ram takes over.

Only the tilt piston is actually attached to the motor -- pushes it up and pulls it down -- the trim pistons just push it up.

The tilt piston doesn't have enough force to hold the motor up when you apply too much throttle, so in case you forget it's tilted up after going thru shallows for example, and put the hammer down, it won't lift the bow so much.

Also, the tilt cylinder has an emergency relief valve designed to allow the motor to kick up if you hit an obstruction at speed.