Have an '03 190 bay with a F115 yammy, that trim wouldn't go down. Went fishing Monday eve, did fine. Left docked in water overnight with tilt up. Had a little light rain over night, not that that matters. Next morning tilt goes down fine, when starts to trim down, sounds like something binding. Could hear motor running but not trimming down. Trim rods would just barely move. Same results with both switches. Acted like hydraulic fluid not allowed to return to reservoir or something. Long story short, loaded on trailer, gave it an hour ride home. Before I tried to work trim again, I tilted all the way up, excersized a trim sensor lever on starboard side. Cracked loose a fluid cap and fluid started seeping. tightened that back up. Been working fine ever since! Any one have a clue what was going on with this? Boat is a recent purchase and repair manual is on the way. Still would like to take it out this weekend. Kind of leary since not sure what the cause was. Motor only has 157hr. trim rods look perfect. Is 15 years old. stuff happens.