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1999 90hp Johnson boat motor Tilt problem All the usual noises but the motor won't come down

Kestrel

New member
Havn't used the motor for about six months and it was left in the up position when I last used it. I press the down switch and all the noises sound the same but nothing happens. I've checked to make sure nothing is in the way or impeding the motor from coming down. Never had a problem before and the boat is not used a great deal.
Th power must be getting there. Is there something that would make it stick or something simple for me to check to determine what the problem may be. Thanks
 
I'm not familiar with the 1999 design BUT if the PTT is the common one that has been manufactured for years back, having two trim rams and one center lift ram, read on.............

(PTT Hydraulic Lockup)
(J. Reeves)
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).
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.
(The Cure)
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.
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.
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.
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.

Also a possibility is.......

(PTT Oil Pump Air Lock)
(J. Reeves)
When the PTT unit is as it should be, the electric motor runs, the manual release valve is closed, the unit is full of lubricant, and nothing works, the usual problem is an air lock under the oil pump Proceed with the following.

Engine in full tilt position. Remove reservoir fill plug screw. Insert a air nozzle up against the reservoir fill hole with rags (or something) packed around it to obtain a tight fit. Apply just a slight amount of pressurized air (10 psi resommended) to the reservoir. This will force the oil under the oil pump to remove the air lock. DO NOT go crazy with the air pressure (15 psi tops!).

 
Maybe open the manual release valve ----------Push the motor down--------------close the valve and try the trim up switch.
 
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