1993 Force tilt/trim question

[tex599]

I have a 1993 Force 90hp engine with a 2 wire tilt/trim motor on a bass boat. The problem is that when underway the tilt will not hold and the prop thrust forces the motor down. Is this normal? I had read through the archives and it mentions that the tilt rams are not designed to hold the motor under power, but you should rely on the trim (I think this is the fatter cylinder in the middle) to hold motor. I have not had an outboard motor before only inboard/outboards and could not see the motor when moving. Please let me know if this is normal or if I should look into rebuilding the pump.
Thank you

 

[QuadManiac]

Re: 1993 Force tilt/trim question

Tilt cylider does not have the strength to hold the motor under way, but the trim cylinder should. If it doesn't you have a bleed down, probably in a check valve at the pump end.

 

[RRitt]

Re: 1993 Force tilt/trim question

trim should hold up to 150HP. being a 1993 it was built by mercury and could have either oil (tan/golden/brown) or ATF (red) as fluid. If ATF and your tilt is not bleeding down then very strong possibility that trim piston ring is going out. Which is very bad news. If tilt is bleeding down then that is actually good news. It would mean that you can get fixed for cheap. If trim piston is breaking up due to ATF then the only safe bet is complete system overhaul. ATF makes the rubber crumble and sends debris throughout system. The debris can get lodged in pump and cause anything from bleed down to complete failure.