I recently bought an 89 17' Renken for a steal. She runs good; however the tilt/trim will only hold the motor up for about 4min before she slowly drops down. When I asked the owner where the resivior was for the hydraulic fluid was he pointed at a black cylinder mounted next to the engine and stated he never messed with it in the 14+ yrs he had the boat. I am assuming that it is an all in one piston and hydraulic resivior. It is shaped like a car stater with the elictal on the top of it and two hydraulic line on the bottom. There is a "knobb like" screw/bolt head just below the half way mark on the cylinder. I am assuming that this is the fill hole for the fluid. Some one told me to fully raise the motor and secure it then remove the fill hole to add fluid, but this doesnt make sense to me. If the piston is pressing the fluid down would it not make sense to fill it when the motor is down? How do I check the fluid leve? Is the above mentioned issue possible that air has gotten into the line over time and all she needs is to filled back up or could it be something else. Please help. I cannot find anyting on the net that can come close to leading me in the right direction. If needed I can take pictures of the cylinder I am mentioning. Thank you for all and any help.
