1990 Force 150hp outboard trim question

[sshotgun]

I have a 1990 Force / US Marine 150hp CFI Outboard Motor .... Model # 1501X90C .... Ser. # 020451 .... It is installed on a 18.5 foot bass boat ... I know it is normal for the power trim to release its self down as throttle is applied ... the problem is I can't raise it enough to get the boat to plane out completely ..... I have added a wedge , but still mot enough ...

Question .... is there any way to by pass the bleed down on the hydraulic pump for the power up trim ? Or is a bolt on power tilt and trim the only way ??? ... So far I can't find one of them that is rated for more then a 130hp ... any out there for a 150hp ?

Thanks Doug

 

[pnwboat]

Re: 1990 Force 150hp outboard trim question

The motor should stay trimmed at what ever position you set it at. Sounds more like you have a bad seal in the hydraulic Tilt/Trim pump. If you post a picture of the Trim/Tilt pump, there may be some folks that can help you out.

 

[jerryjerry05]

Re: 1990 Force 150hp outboard trim question

Your stock pump should do the job.
If it's drifting down then the pump needs to be rebuilt.
RRitt repairs these pumps.He'll probably be on and reply.
If you have the original pump it's better to get it rebuilt as the aftermarket won't last as long.

 

[RRitt]

Re: 1990 Force 150hp outboard trim question

if it drifts down on trailer it is most likely pump. If it holds on trailer but goes down with throttle then check to make sure your transom doesn't have a divot or that the strike plate (up underneath engine where the trim piston hits) hasn't split or wallowed.

 

[sshotgun]

Re: 1990 Force 150hp outboard trim question

OK ... I was told the 2 little lifts were just for trailering and when motor was not running .... and the big one in the center was for trim ... If you start the motor higher then the center one and put it in gear .... it quickly lowers to the center one which holds in its highest position .. which isn't very high ... and not enough to trim out the boat correctly ... check out pictures ...

On the motor ... its a 1990 , but has been in a crate till last year ... and has under 10 hours on it ...

 

[RRitt]

Re: 1990 Force 150hp outboard trim question

that is a full power trim. trim system won't work if it isn't up against a backing plate. Your backing plate need to able to take 150HP. Without a backplate the system rotates under load and the trim shaft slips off strike plate.

 

[pnwboat]

Re: 1990 Force 150hp outboard trim question

The Jack plate that you have was not designed to work with the Force mounting bracket. Like RRitt stated, the back side of the trim cylinder (which is the short cylinder with the 5 bolts holding the top cover on) was designed to be resting solidly against the transom. Without that support, the weight of the motor pushes against the end of the trim ram when it is extended and makes the whole assembly rotate upwards which causes the motor to drop down.

You could get it to work but you need to install a plate behind the mounting bracket and trim cylinder that is sturdy enough to withstand the force. Kind of like if the mount and trim cylinder were mounted flat against a solid transom.

 

[sshotgun]

Re: 1990 Force 150hp outboard trim question

THANKS !!!! .... you guys are right ... I used a bar and carefully put presure on the top of the trim cylinder ... it rotated down and now will lift enough to trim the boat I beleive ... looks to be a easy fix with the plate ... RIGHT ON !!!!!
Doug