actuator problem

[galeus]

As a back up to our trusty BMC 1.5 diesel we have a 10hp o/b electric start that is raised and lowered in the water by an actuator.

http://www.youtube.com/watch?v=OnyXMznqpwY

http://www.youtube.com/watch?v=3rlTeRJ1-mA
'
This actuator is not designed for marine use so I have done my best to marinise it, but it is not perfected yet.
It is actually the second unit and in it's third year.
At this point in time it is trying to work ie I can see the torque trying to move the o/b bracket but no good, so I will bypass the actuator and operate it by rope and gravity if needed
until the end of our trip.
Question. Inside the unit as well as the motor and 'screw jack' type mechanism is a circuit board which last winter when I serviced it had signs of corrosion, but it still worked.
Do you think the actuator would work without the circuit board, if I wired straight to the the motor and operated the switch very deftly, (so as not to blow a fuse).
Anything that makes it simpler would surely make it more reliable.

Thanks Richard

 

[rogerthebodger]

I in fact made a screw actuator last year for my engine access hatch and it used a windscreen wiper motor which is a permanent magnet motor so reversing the motor is be reversing the + and - leads on the motor. This can be done with a 2 pole change over switch 3 position centre off. The circuit board will include relays controlled by limit switched or other type of sensor to prevent over travel in either direction.

If you disable these limit switches you could end up burning the motor out of damaging the screw/nut in the actuator its self.

I don't have any pics of diagrams of my actuator with me they ar on my boat 600 km away.