Re: drive trims down by itself
Tim, Trim Cylinder leak down may be fixed, but you need to find out what's malfunctioning. The possible causes: Bad piston seal (or rod seal) in one or both trim cylinders or bad trim control valve. <br />If no oil leaked into the water, the rod seals are probably OK.<br />Now to isolate a bad piston seal, haul the boat, disconnect the hydraulic lines for one cylinder and plug them. Pump up the outdrive and wait to see if it leaks down. If so, repeat with the other cylinder. If it still leaks down it is either both cylinders(unlikely) or the trim control valve. At this point it is probably a good idea to engage a professional who can test the trim control valve. <br />PS There are trim cylinder repair kits available for some standard units.
