86 force 85hp trims up but falls down

[deweydog]

I have an 86 bayliner with an 86 force 85hp motor. it trims up but falls down. could this be a hydraulic leak ? I don't seen any fluid on the ground. are the shocks weak and need replacing ? checking to see if anyone had same problem and how they solved it. <br /><br />thanks much, Dwight

 

[chuckz]

Re: 86 force 85hp trims up but falls down

Sounds like a bad internal seal in the trim cylinder. You wouldn't see any oil on the ground because it's an internal leak. The cylinder needs to be rebuilt.<br /><br />BTW you should be using SAE 30 non-detergent oil. If you're using thinner oil, drain it and replace with the 30 weight oil.

 

[roscoe]

Re: 86 force 85hp trims up but falls down

Likely is a dirty check valve or worn orings in the base of the pump. Becarful when you take it apart as spring and ball bearing will be poppong out.

 

[chuckz]

Re: 86 force 85hp trims up but falls down

Roscoe,<br /><br />Took my pump completely apart to find out if the deteriorated o-ring crud was from the pump or from the cylinder. The only o-rings in the pump are around the check valve body. There are no internal o-rings. It is not necesary to disassemble the pump.

 

[roscoe]

Re: 86 force 85hp trims up but falls down

Ok, sounds good to me.<br />Too many force tnt "systems", not enough experience working on them.

 

[tazzzzman]

Re: 86 force 85hp trims up but falls down

you need to replace the valvebody