help with 90hp force power trim

[archery1]

I have been searchin internet on how to drain then fill my power trim. it is a single cyinder system. I has a knurled bolt towards top on side.. then a hex head(female) screw on lower part of cylinder. I am pretty sure i loosen kunrled bolt on side to fill but do i loosen that bolt that takes a allen key to drain it?
Thanks for any ones help on this in advance/

 

[jerryjerry05]

To help flush the system, you need to loosen one or two lines and cycle the unit.
.​Keep adding oil as you go.
It's gonna take a while and a bunch of fluid to clean it out.

BE VERY CAREFUL WHEN LOOSENING THE FITTINGS.
Use a line wrench and not a cheap one.
Model and serial#, year always helps.

 

[pnwboat]

I wouldn't remove the hex plug on the lower part of the cylinder. From the parts break-down, it looks like that there may be some small parts used to control the trim that are held in place by the hex plug.

 

[archery1]

thanks for the help.. the metal plate on mount is unreadable. it is completly silver.. nothin is visible/ I ran to local boat motor repair place.. (lancaster marine) they sold me a bottle of mercury/force power trim/steerin fluid. took out knurled bolt and loosened bottom line to get all i could outta it. refilled with this fluid they sold me. now the motor comes up but dont go down properly. it either stick or when it does come down it jumps. still cant get it to come down all the way. ..back to the drawin board!!!!!1

 

[archery1]

well messed with this for a few hours today. filled fluid up. the motor goes up great. Has a problem goin down. If i tilt motor the whole way up. it doesnt want to come down at all. If i loosen one of the lines an let alittle fluid come out ,an motor starts to come down. then tighten line and tilt down it goes alittle bit then stops. i tilt up then fast down an it goes alittle bit. i keep on doin that and each time i get it to come down a inch or so. So i inserted a hex key into lower bolt. took bolt off (i think thats called a relief valve) has a little spring inside contained bolt . now whats inside resivoir is a little round part. has a oring around middle with a point on each end. not sure what its called?? any way. could this be the part thats wrong? i have had this motor trim and tilt put on a few years ago and it has always had troble goin down but if i quickly trimmed up and then down it would go down to where i needed it to be. now since i drained and put new fluid in this not going down the whole way even if i tilted up and then down quickly. Pump runs great. battery is fully charged. its on a 90hp force motor. twin cylinders hooked up to the pump.

 

[jerryjerry05]

If it's a 90 it was made after 89.
​They started the 90 in 1990.
Usually if the trim jumps and jerks?? the fluid is low?

Since it's a single ram. you should post pics so we know what were working on.

There might be some dirt in the system and it's blocking the pump??

Post pics.
Got your message.

 

[archery1]

here are sm pics.. this has 2 cylinders the female hex key bolt has a spring loaded pin hole on end. behind that is a worm gear sort of slot on either end with oring in middle. o ring looks good. there is another female hex ket bolt on backside of resivoir bt i cant take off unless i take the pump off of boat. Hope these help
thanks

 

[archery1]

pics

 

[archery1]

was wrong in first post. it is a 2 cylinder model. not 1 as posted /sorry

 

[pnwboat]

OK, that is the older design 1 model. I would suspect that the shuttle valve is not working like it should.

If you look at the top of the Force & Chrysler Forum, you'll see a subject called "Force & Chrysler FAQ and other great information" Under that there is another post called "Force 3-wire Tilt and Trim system with shock absorber system "test & repair" procedures.http://forums.iboats.com/forum/engin...trim-drop-help by pnwboat & Jiggz"

Click on the link and it has all of the info on how to repair the valves. NOTE: I would advise you not to unbolt the 5 bolts that hold the internal pump together. Most likely you just need to replace the "O" ring on the shuttle valve or maybe clean out the bore that the shuttle valve rides in. While you're at it, I would also replace the small "O" ring on the two directional valves too. They are a common failure item.

 

[jerryjerry05]

That PIC of the pump makes a lot more sense.
​Follow what PNW suggested.
The year of manufacture is under the coils and pack on the side of the cylinder housing.
One pic of the lower unit will help ID it also.

 

[archery1]

Jerry. the lower unit isnt the same year of the motor. It is from a bigger force motor. I was wonderin why i never got alot of speed outta boat .Thats why it has the wrong lower unit on it..only gettin 33-34 mph outta it on my 16' deep v aluminum boat

 

[jerryjerry05]

If it has a different gear ratio??
​You'll need to re-prop.
Make sure the tach is working and take her for a spin.
Get up to wide open and see what the rpm's are.
Then adjust the size from there.