I have a 50hp evirude model #50172s with a lower unit that is stuck in gear.This is an electric **** type and I have taken the lower unit off. The solanoids seem to be O.K. I worked them and they move their plunger.(right word?). With the solonoids and thier plungers out the lower unit is still stuck in gear. Is there something inside that is broke? Is there something that goes wrong with these units that commonly happens? How many special tools are needed to work on this unit? (besides a manual).Are parts available?Thanks for any help.