My Yamaha raises up while in reverse?

[Greg V]

Hi all,I have a 2005 Yamaha 90hp 4 stroke. I've just noticed that if I increase the throttle while in reverse the engine starts to lift from the torque of the prop, then will drop down hard when I ease off the throttle. I also noticed some "bounce" to the motor while at speed when there is some chop on the water. When I use the tilt/trim at the ramp the motor lifts up fine. I have checked the manual release screw on the side and it is tight. Does this sound like low fluid or something else? Thanks, Greg

 

[rodbolt]

Re: My Yamaha raises up while in reverse?

most likly is the tilt ram shock valve has failed. when it comes back down does it return to its previous position or does it drop to the full down position?<br /> but the causes can be many.

 

[Greg V]

Re: My Yamaha raises up while in reverse?

Hi Rodbolt, when it comes back down it appears to return to it's previous position. I can trim it to any postion and it will stay there without dropping down. It just wants to lift "up" with the prop spinning in reverse. Thanks, Greg