hydraulic pump - convertible top- replacement for linear actuator

[PieterO]

Hi,

I have sort of the same problem question. I want to add pypilot to my existing hydraulic steering. 12V hydraulic pumps are very pricy.

My situation
I have an catamaran with hydraulic steering.  The steering wheel is the hydraulic pump with built in reservoir. The rudders are connected via a tiller. A hydraulic ram is mounted to that tiller.

I want to make it like the Schema below (withouth part 3). 


I want to buy a trailer hydraulic pump like this which is reversible and made for trailers like the picture below. Those units are 300 euro's. My questions are:
Is that feasible and do i forget something?
Can pilot just control the buttons via a relay or directly? It will be on 100% always then. 
Do i need check valve's so that the fluid wont spin the when when the auto pilot is working?


The motorpower is 1.6kw Rated and 3.0 kW max. @12V that is 133/250  Amps. Wonder what the true power draw is for my small cylinder.
I don't like the large fluid container, I want to try to get rid of it since there is already a fluid tank in my wheel. 




Now, another option is to use a more regular hydraulic pump like this one: https://www.cactusnav.com/universal-auto...22520.html
That does require a motor driver, but I have to find out the amperage of te system.


Thanks in Advance.