79 Evinrude tilt/trim problem

[BBMerlin5091]

I just bought a 79 Champion fish and ski with a <br />115 hp Evinrude, it had multiple wiring problems with it when i got it, but i have solved all of them and everything was working fine up until about a week ago. I was taking it out for the first time and i had the engine tilted up too far for the travel lock, so i tried to tilt it back down and it would not move. It goes up just fine but will not come back down. The motor is engaging and seems to be operating normally, no strange noises or leaks that i can find....possibly low on fluid?????????? as this is my first boat, i am totally unfamiliar with the inner workings and don't even know where to begin to check the fluid level if that is even the problem. <br /><br /><br /> any help would be greatly appreciated

 

[ob]

Re: 79 Evinrude tilt/trim problem

Can you hear the relay under the motor cover clicking when you try to trim down?<br /><br />Edit: Nevermind .I reread your post and see that you indicated the tilt motor was running.

 

[Joe Reeves]

Re: 79 Evinrude tilt/trim problem

(PTT Hydraulic Lockup)<br />(J. Reeves)<br /><br />If the engine has been trailered without having both of the trim rams pulled in, or trailered without even having the engine being supported by the trailering support, it is possible for the PTT to encounter a hydraulic lock up. The slight up and down motion, when trailering allows over 1700 psi of oil pressure to build up on the wrong side of the oil pump. Since the oil pump cannot exceed that 1700 psi, the unit is effectively hydraulically locked into position (the elec motor runs and does nothing).<br /><br />The proper method for trailering is to have the engine in a full tilt position and resting on the trailering support bracket, then have both trim rams pulled in to a point where the engine makes a jerking motion. At this point, immediately take your finger off of the PTT trim switch. Now, quickly and sharply, tap the PTT up button. This removes the vast majority of down hydraulic pressure but at the same time, the engine is solidly locked into position and cannot rock up and down.<br /><br />(The Cure)<br />Have the engine in the up position and supported so that it cannot fall. Look straight at the PTT assy.... you will see what looks like a large slotted screw on the port (left) side of the PTT assy, but which is in fact a check valve. Remove that valve and what you find inside which is a shuttle valve, and a spring on each end of that shuttle valve.<br /><br />After you've removed those items, look straight inside of that chamber. You'll be looking at the reverse side of another check valve. Look at the hole in the backside of the valve you removed. You will need a punch that will fit inside of that hole.<br /><br />Now, place the punch inside of the hole in that check valve that is still in the unit, and tap it rather sharply with a hammer. It will take quite a rap but the idea is to unseat the valve to release the hydraulic pressure. Watch your eyes as when you do release the pressure, it will have a tendency to spray out somewhat.<br /><br />After releasing the pressure, reassemble the shuttle valve, springs, and outer check valve. Fill the oil reservoir with PTT fluid, having the engine in the extreme full tilt position. That's it.<br /><br />The reservoir fill is the large slotted screw on the starboard (right) side of the PTT assy.

 

[BBMerlin5091]

Re: 79 Evinrude tilt/trim problem

Thank you very much for the reply Joe. I went out and tried it this afternoon, i didn't get any pressure release out of the check ball when i tapped it with the punch. The ball moved roughly 1/4 of an inch, is that about normal? I would think that the check ball would not move at all if it had a lot of pressure behind it. it's got me a little confused now<br /><br /> again thank you for the help

 

[Joe Reeves]

Re: 79 Evinrude tilt/trim problem

Yes, if the problem I described existed, the ball check valve would have had quite a bit of resistance to the punch and hammer, and when tapped, fluid being released somewhat under presure would have evident. Apparently you don't have that hydraulic lockup type problem.<br /><br />Chack and fill the reservoir with the engine in the full up position. When engaging the "down" button of the switch, check to see if the trim rams are pulling in. If so, the engine is sticking somewhat at the steering tube assemble. If this is the case, after the trim rams are in, the tilt cylinder will pull the engine down.<br /><br />Let us know what you find.

 

[Sherman]

Re: 79 Evinrude tilt/trim problem

I have this same motor and often have this condition caused not by the hydraulics but by binding of either the tilt pin or the pins at the ends of the cylinder. Will this motor go down if you give it some assist by hand. If it does I would lubricate all three pins with some good lub.

 

[BBMerlin5091]

Re: 79 Evinrude tilt/trim problem

That worked Joe!...Thank you very much for all your help. Once i filled it up, both rams pulled in, and down it came. It's working perfectly now, up and down. I lubed the steering bar, and all of the fittings. <br /><br /> Once again, thank you for your help, and i'm sure i'll be talking to you again.<br /><br /> Duane Beechum<br /><br /> GONE FISHIN'!!!!!!!!!!!!!!!

 

[walnuts55]

Re: 79 Evinrude tilt/trim problem

100hp with same problem, Thanks Joe I will go try your fix and let U know if it works.

 

[hbahn]

Re: 79 Evinrude tilt/trim problem

I have this same motor and often have this condition caused not by the hydraulics but by binding of either the tilt pin or the pins at the ends of the cylinder. Will this motor go down if you give it some assist by hand. If it does I would lubricate all three pins with some good lube.

I have the same prob with a '75 115 HP but the motor will not go down with hand assistance. It will lower (by motor/pump) an inch or 2 and then appears to be hitting a stop. There is a release lever on the port side, but that doesn't help. I understand there may be a small tab that folds down to lock it into place for trailering, but am not sure were to look.
Boat is in the water, some miles from a ramp so I am hoping to get it down enough to get it back on the trailer.