Tilt/Trim problem

[dragon2161]

Tilt/Trim was working properly until I hit a sandbar with the motor at a down position. The Tilt/Trim still operates as normal at a halt, but will only trim high enough just prior to plaining the boat before it drops back to the down position without my control. There are no visible leak on any of the cylinders and or decrease on the fluid level. Any advice is greatly appreciated.........HELP <br /><br />1986 OMC 1.6 Seadrive<br />17'1 cc Sport-Craft

 

[demsvmejm]

Re: Tilt/Trim problem

Sounds like you popped the piston seals in the trim cylinders. These are dual acting cylinders, meaning there is hydraulic pressure on both sides of the piston. The two chambers are seperated by a seal. If this seal becomes damaged then fluid passes back and forth as it sees fit. Sounds like there's enough of a seal to provide hydraulic lift in a static state, but once the boat is moving and the load increases due to inertial forces, the seal can no longer hold the hydraulic pressure and allows fluid to pass by, thus the outdrive falls. Unfortunately there is no real simple way to test for this. And the specialized hydraulic pressure gauge is very expensive. Good luck, and hopefully some other members may have had similar experiences and can offer some help too.

 

[dragon2161]

Re: Tilt/Trim problem

I think you are right; based on the way it's acting along with your analysis it makes sense. I am still able to use it with speed; it just takes longer for it to plane. Thanks David!