Johnson 115 1979 tilt/trim problem

[breezland]

The engine is stuck in the up position. the tilt trim motor makes nosie but does not move the engine either up or down. First of all is there someway to override the power tilt system so i can get the engine back down so i can get the boat out of the water. It seesm to me that the moter is running but not pushing the hydralic fluid. The power trim system is located inbetween the transom bracket. I have read some past posting on this subject and it seems like these parts are expensive.

 

[Hooty]

Re: Johnson 115 1979 tilt/trim problem

There's a relief valve on the outboard starbord side of the clamp. It's shown in the manual<br /><br />c/6<br />Hooty

 

[mutron77]

Re: Johnson 115 1979 tilt/trim problem

When you tilt your motor up for trailering or storage, flip up the trailering bracket and then trim down until the pistons retract all the way back into the cylinders. If you don't do this there is a valve in there that loves to stick, especially in hot climates and your trim will lock up. On ours it happened once. I believe we just opened the relief valve refilled with lube and then were carefull from then on. I think on some systems the motor has to come off to fix the problem, and that would be nasty.

 

[breezland]

Re: Johnson 115 1979 tilt/trim problem

thanks when i put the engine up last time i did not use the trailering lock which i usually do so what u say make sense to me. i will turn that relief valve and hopfully the engine will drop. i do not believe that screw has ever been turned in over 20 yrs.

 

[Joe Reeves]

Re: Johnson 115 1979 tilt/trim problem

********************<br />(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 />********************