Trim is stuck!!!!

[fitz73222]

Fill it to the bottom edge of threads of the screw hole! Use power trim fluid or power steering fluid. I would use automatic transmission fluid as a last resort since it is not true hydraulic fluid. You will have to run the trim up and down several times and keep checking the fluid until all the air bleeds out. The fluid will look foamy or full of suspended bubbles. The pump will cavitate and make noise until all the air is purged. Next will be to understand why there was no fluid in it to begin with. Glad you are making progress!!!

Fitz

[wingtime]

I believe Mercury calls for ATF.  At least mine does.

[The Rodfather]

well, the resevior didnt take much fluid at all.  maybe a tablespoon or two.  im beginning to think the motor is weak.  whats the proper way to bleed the system now that i can tilt all the way up?  the motor comes up fairly easily with a little help from my hands when the trim button is being pressed.   the banging noise was the two little pistons maxing out im sure,  and when it is time for the main piston to work on its own,  it seems like something prevents that from happening.   the motor kind of starts to squeal and sound like it begins to struggle at that point.  but again,  if i assist it with my hands, it comes up very easily. . . like as if the two little pistons were still acvtive.   so now im down to . . . . does it need to be bled, or. . . do i need a new trim motor?   THANKS. You Guys Rule

[fitz73222]

The system is self bleeding internally. Do you have the manual release screw tightened back up when you are raising and lowering the system. It still sounds like air is in the system. Your battery and connections need to be checked. A power trim system uses alot of amps to go up and down. A weak battery or bad connections can also add to the weakness of the system. You should have a fully charged battery that shows at least 12.6 - 12.8 volts on a volt meter and clean, tight connections.

[John Jones]

good info Fitz.

You will not get all of the air out of the system until you can run it all the way up and down several times.

I went through this with a friend last year on a used boat he bought without even cranking the motors.  Older twin Yamaha 130s.  The port motor would not go all the way up.  It would not come back down unless I added my 185 lb. to the skeg.  We worked 4 hours helping it up then forcing it back down.  Then hitting it with a grease gun again.  We never did get that motor 100% free.  Now and then it will hesitate on the way down, then fall a couple of inches with a clunk.  His issue has nothing to do with the hydraulics. He refuses to change out the tilt tube.

[wingtime]

Is there some sort of a valve that switches over the hydraulics to the tilt cylinder when the trim cylinders are maxed out?  or does the fluid just flow from them into the tilt cylinder?    

The tilt tube is not that big of a deal to change out but you need a hoist to hold up the motor while you do it.  Also does your motor have a stainless tilt tube?  If not you can get them for about $100 new.

[John Jones]

It's been 35+ years since I was trained in hydraulics and most of that gray matter has leaked out now.

No physical switch over.  The twin trim rams have more lifting force than the single tilt ram.  Pressure is applied to all three but the trim rams actually make the motor move up thru their range.  Once they bottom out the only place for the hydraulic fluid to go is the tilt ram.  Trim rams need more force because they have to push against the propeller force if you trim while running.  Dual rams also move slower because it takes twice the fluid volume to move them.  This gives you a finer control.  

My son has an older Honda 45 4-stroke on his Mitzi Skiff.  That motor only has a single tilt ram and no trim rams.  It's a real PITA to adjust trim while running because it moves too fast.