Hi Everyone, I just joined and have a basic question for you all. 
I purchased a 1991 Glastron 19' boat with a mercruiser 4.3L engine and Alpha1 stern drive (its my first ever boat). The electrics have been seriously attacked by previous owners.
I have now repaired most of the damage and everything seems to be working as it should.
I recently cleaned the trim position sensor (on the starboard side of the stern drive gimbal) so that my trim gauge now goes up and down and correctly shows the position of the stern drive. There is a position switch on the port side of the gimbal which according to the wiring diagram is connected in series with the tilt control.
So to get to my question.. The throttle has two 2-way toggle switches mounted on it, one is marked TRIM (up/down) and the other TILT (up/down). The trim switch allows me to raise or lower the propellor as far as is mechanically possible by the hydralics. The tilt switch allows me to lower the propellor as far as is mechanically possible, but to only raise the propellor to a preset position (controlled by the position sensor switch on the gimbal).
I purchased a Handbook for this motor/sterndrive and it says to adjust the position sensor so that the tilt switch stops when 6.5" of the raise/lower hydralic ram is sticking out. This doesn't make any sense to me so I wanted to ask what are the intended functions of tilt and trim?
My assumption was that Trim is used to trim the propellor to any position when the boat is moving. Tilt is just used to raise the propellor out of the water when you want to put the boat on the trailor. Therefore I expect the tilt control to stop just before the propellor has reached it's maximum height, which is about 11" of hydralic ram showing, not 6.5".
As this doesn't match with the manual, I now assume Tilt is used for something else?
Could anyone please explain the purpose of the Tilt control on a mercruiser stern drive? And when it is meant to be used for? Trim gives full range of mouvement, Tilt has a restricted range of mouvement, why do you need tilt? or should what I am calling Tilt really be called trim? As the electrics had been messed about with, these 2 switches could easily have been switched around by me or a previous owner.
Maybe trim is used to raise and lower the propellor and tilt is used to change the propellor when the boat is moving, then a maximum of 6.5" of hydralic ram showing, would make sense as it would not have the propellor coming out of the water by very much? Just trying to understand what seemed a very simple problem!!
Many thanks.
Gary
I purchased a 1991 Glastron 19' boat with a mercruiser 4.3L engine and Alpha1 stern drive (its my first ever boat). The electrics have been seriously attacked by previous owners.
I have now repaired most of the damage and everything seems to be working as it should.
I recently cleaned the trim position sensor (on the starboard side of the stern drive gimbal) so that my trim gauge now goes up and down and correctly shows the position of the stern drive. There is a position switch on the port side of the gimbal which according to the wiring diagram is connected in series with the tilt control.
So to get to my question.. The throttle has two 2-way toggle switches mounted on it, one is marked TRIM (up/down) and the other TILT (up/down). The trim switch allows me to raise or lower the propellor as far as is mechanically possible by the hydralics. The tilt switch allows me to lower the propellor as far as is mechanically possible, but to only raise the propellor to a preset position (controlled by the position sensor switch on the gimbal).
I purchased a Handbook for this motor/sterndrive and it says to adjust the position sensor so that the tilt switch stops when 6.5" of the raise/lower hydralic ram is sticking out. This doesn't make any sense to me so I wanted to ask what are the intended functions of tilt and trim?
My assumption was that Trim is used to trim the propellor to any position when the boat is moving. Tilt is just used to raise the propellor out of the water when you want to put the boat on the trailor. Therefore I expect the tilt control to stop just before the propellor has reached it's maximum height, which is about 11" of hydralic ram showing, not 6.5".
As this doesn't match with the manual, I now assume Tilt is used for something else?
Could anyone please explain the purpose of the Tilt control on a mercruiser stern drive? And when it is meant to be used for? Trim gives full range of mouvement, Tilt has a restricted range of mouvement, why do you need tilt? or should what I am calling Tilt really be called trim? As the electrics had been messed about with, these 2 switches could easily have been switched around by me or a previous owner.
Maybe trim is used to raise and lower the propellor and tilt is used to change the propellor when the boat is moving, then a maximum of 6.5" of hydralic ram showing, would make sense as it would not have the propellor coming out of the water by very much? Just trying to understand what seemed a very simple problem!!
Many thanks.
Gary
