Johnson tilt/trim

[Jrm]

2000 Johnson 150 ocean pro tilts up and down no problems. Will stay up for days no problem however when down and I go in reverse the motor slowly walks out of the water. Was a lot worse but I changed the tilt piston per the book and some advice from mechanics, I have been told by one mechanic it is the Oring on the manual relief screw, another said no because it holds it's self up. Any help is appreciated thanks.

 

[Boobie]

Normally when that happens it's the manual relief valve from not being tight or bad.

 

[Jrm]

Yea I found the middle Oring missing replaced it haven't tested on water yet but I can't pick it up by hand anymore I'm confidant that was the issue that for the reply.