Which helm for single unbalanced rams

Hi,

I have a single marine machine 9" stroke cylinder mounted on my Merc 2.5L EFI. I have used this in combination with a Seastar 2.4 helm pump, but it seems that I can't get all the air out of my system.
I have read that several people use this combination and don't report any problems, but from my understanding, the Seastar helm don't have enough reservoir capacity to hold the needed oil.
When the cylinder is pushed back in, the excessive oil is pushed out of the helms fill hole. Then when i turn the helm the other way and extend the cylinder rod, the oil level drops too much in the helm and makes room for new air to access the system.
It would be a good solution for me if the 2.4 helm could be used in combination with a reservoir tank, and then pressurize the system, like the hynautic does. Is this possible?
I also have a capilano 1275V helm unit on hand, since I've seen this helm used in combination with single unbalanced ram in several boats as well. Will this helm operate the same way as the 2.4 helm regarding reservoir capacity? Or will I need a reservoir tank either way?

Any help would be truly appreciated.


Best regards
Christian

You need a reservoir with the seastar. Capilano you do not.

The reason you can't get all the air out is because the ram is emptying the helm allowing it to suck air.

Having both helms at hand, use the Capilano!

thank you very much for your help guys. I'll be putting on some glass on my stv euro dash tomorrow, and install the Capilano one of the following days.