1987 force 125 h.p.

[leander hutchinson]

hi, i have a 1987 force 125 h.p outboard, i have been having trouble with the tilt&trim droping down. i fallowed the advice of replacing the little o-ring in the pilot valve and it worked.now the unit goes up and stays there out of the water.the unit does'nt work when underway or sitting at the dock. it seems strange that it will work out of the water fine and does'nt drop anymore.i had both shocks rebuilt with new o-rings also. now i am stumped where to go next. can anyone help me.

 

[bentle]

Re: 1987 force 125 h.p.

Can you hear the pump working at all while just sitting at the dock? With motor not running.

 

[jerryjerry05]

Re: 1987 force 125 h.p.

Not sure whats happening???
Drifting down??If so the hydrolic pump is probably bad.
There are test procedures for the leak down of the pump and the tilt cylinder.
I will post it tomorrow.Maybe RRITT will explain it first.J

 

[leander hutchinson]

Re: 1987 force 125 h.p.

Can you hear the pump working at all while just sitting at the dock? With motor not running.

thats a hard one to answer,because i have a bad left ear and all i could say was that all i could hear was the motor running

 

[leander hutchinson]

Re: 1987 force 125 h.p.

i don't think the hydrolic pump is bad,because when the boat is on the trailer,the motor goes right up and stays there and it does'nt drift down at all.

 

[bentle]

Re: 1987 force 125 h.p.

Ok. But with the engine off and sitting in the water you can't hear the pump trying to work at all? Sound like a bad pump or bad electrical prob. How do the wires look going into the pump. Any bare wires? Also what kind of oil did you refill pump with?

 

[jerryjerry05]

Re: 1987 force 125 h.p.

Directions for leak down for the tilt ram and the hyd motor. One more pic in the next thread. Not in order you have to figure out the right order.

 

[jerryjerry05]

Re: 1987 force 125 h.p.

#5 of 6. Hope this helps.

 

[leander hutchinson]

Re: 1987 force 125 h.p.

the wires going into the pump look fine.the oil i used was 30wht non det. motor oil

 

[leander hutchinson]

Re: 1987 force 125 h.p.

the thing i don't understand is,what doe's the trim cylinder do and what part of system doe's it perform.could this be the problem and needs rebuilding.also the boat seems to not have enough power to get up on plain, it just goes about 35 m.p.h. with the lever all the way down.seems like it should be able to move right out there.

 

[bentle]

Re: 1987 force 125 h.p.

The trim is for raising motor and helps get front of boat up. Very useful on a day when waves are high. Also trimming motor up will increase mph a bit depending on number of passengers. 30 wt. Motor oil is to thick. I would drain that oil and go with a good outboard tilt trim oil. I had a prob. With mine similar to your. Found out my oil was to thick so I drained and refilled with marine grade tilt trim oil and prob. Solved. On cold days oil gets really thick and its hard for pump to get oil to cylinders.

 

[celtic gelf]

Re: 1987 force 125 h.p.

if you"re not planing out.. are you sure the motor is actually trimmed all the way down....It's like your trimmed up some which you do for wakeboarding to pull bigger wakes.

 

[leander hutchinson]

Re: 1987 force 125 h.p.

thanks, i'll drain the oil out and try the marine grade oil.at this stage i'll try anything.

 

[leander hutchinson]

Re: 1987 force 125 h.p.

i'll have to check how far down the motor comes,maybe the trim cyliner is'nt working.everthing else has been rebuilt.

 

[foodfisher]

Re: 1987 force 125 h.p.

the thing i don't understand is,what doe's the trim cylinder do and what part of system doe's it perform.could this be the problem and needs rebuilding.also the boat seems to not have enough power to get up on plain, it just goes about 35 m.p.h. with the lever all the way down.seems like it should be able to move right out there.

Tilt is faster but weaker. Won't hold up against prop forces. Used for trailering or storing w/lower unit out of water. Trim is slower but much stronger. Used to fine tune travel for fastest or smoothest ride. Trimmed down will get you up and over the "hump" and onto plane faster. Then trim out to relieve the bow from plowing. Between plowing and porpoising is a sweet spot that will change w/conditions, rpms and speed will determine this. Don't know what hull or prop you've got but 35mph sounds about right for top speed. ps 30 wt nondetergent works fine in my '86 125. but I live in a warmer climate.

 

[leander hutchinson]

Re: 1987 force 125 h.p.

the boat is a 1987 bayliner cudi cabin. the length is 21ft

 

[leander hutchinson]

Re: 1987 force 125 h.p.

the main problem is i can't get the lower unit up in shallow water,to avoid hitting the prop.i'm worried about doing damage to the prop or the drive gears

 

[leander hutchinson]

Re: 1987 force 125 h.p.

when we talk about the tilt and the trim,i know this is a dumb question, but, i only have a toggle switch for up and down.how does the trim come into play.should'nt there be a switch to control it.

 

[foodfisher]

Re: 1987 force 125 h.p.

One switch controls both, from all the way down, up activates the trim until it reaches its upper limit, then tilt takes over and raises the motor faster to it's upper limit. Down is the reverse. Check to make sure the tilt ram is hitting the steel plate fastened to the inside of the lower. If you're worried about shallow water in a 21' boat, you don't need to be there.

 

[leander hutchinson]

Re: 1987 force 125 h.p.

i have no choice about the shallow water, to get to the dock at the families cottage it is real shallow.