Re: Jammed tilt/trim backing down boat ramp
Hard to say. There is a pressure relief valve (or two) on most units which breaks away if an underwater obstruction is struck. It may have jammed open. But that's for forward movement strikes. Your strike is reverse.
One thing you might try is to thoroughly wash and dry your lift hoses (2 each side of outdrive connecting to pistons), then disconnect the hoses to your lift pistons and stick them in a container of fresh trim fluid.....Merc outboards uses ATF (not picky about which kind) or OEM fluid. Ends need to be submerged.
Then get on the up-down control and see if you can get fluid movement in and out of the hoses.
If so, that says your pump and safety valves are working ok. If not will need to give your pumping system some attention. If the pump works ok, you then may have jammed one or both of your lift pistons in the reverse direction.
Pull the "push hoses out of the container of fluid and connect to the forward end of the pistons which, when pressurized, cause the rod to extend....leave the aft end hose in the container of fluid.
Remove the aft end of the lift cylinders (rods) from the outdrive so that they are free to move independently under no load.
Activate the up button and see if the pump can push the piston out...extend the rod. Maybe one will and one won't, or both won't, or both will.
If both will, put it back together and you should be good to go. If one or both won't you will have to fix the cylinders.
Follow up on this and let us know what you find.
Mark