Sea star steering locked out

[12Parker2320]

Launched for the crab opener in Northern California. Complete madness at the ramp as usual on opening day. Tight channel so I start backing down to where it dog legs and I can turn around. I notice my boat isn’t responding to my steering input. Next thing I know my steering is locked to port. I am able to get a line to another boat at the dock and tie off. I trace the entire length of the hydraulic lines and can’t find a leak. I just recently replaced a leaking ram seal and completely bleed the system so I know I’am not low on hydraulic fluid. Back home I try to move the motor physically and it’s still locked with hydraulic pressure. Even after the long road trip back up to higher elevation and all the vibration. I decide to add a little steering fluid at the helm. I was able to add less than an ounce and it started to overflow. Replace the cap and try to turn the wheel to starboard and instantly I have full steering back. Take the boat into shop and they told me there was no leak but my simrad auto pilot pump created bubbles in the lines and eventually caused the sea star system to lock out. I’m guessing the air made its way to the end of one line so I wasn’t able to turn to the other side . Their electronics guy wasn’t there who made the diagnosis when I picked the boat up so I didn’t get a better explanation. Anyone experience this or know why my auto pilot which I hardly ever use created air bubbles in my hydraulic steering lines? And why did adding such a small amount of steering fluid give me steering back? Was that little bit of fluid able to push the air bubble? Sorry for the long post

 

[afitzray]

I can't imagine how the pump would "create" an air bubble unless there was an issue with it. If the diagnostic guy ever gives you any more info I'd be interested to know how that might happen.

Only thing I could think of is that a small amount of air ended up in the system when the ram seal was replaced.

Is it possible for an air bubble to lock up the system if it gets stuck just right at one of the valves? I'm thinking the same thing you mentioned with air or an issue at the end of a line- maybe the air could keep a check valve from closing if gets stuck at just the right spot and the system is completely turned to one side so pressure can only come from one side? And maybe when you opened the helm to add fluid it allowed a section of the system with pressure built up to relieve some of that pressure that allowed the air bubble or stuck valve to finally move.

 

[12Parker2320]

I can't imagine how the pump would "create" an air bubble unless there was an issue with it. If the diagnostic guy ever gives you any more info I'd be interested to know how that might happen.

Only thing I could think of is that a small amount of air ended up in the system when the ram seal was replaced.

Is it possible for an air bubble to lock up the system if it gets stuck just right at one of the valves? I'm thinking the same thing you mentioned with air or an issue at the end of a line- maybe the air could keep a check valve from closing if gets stuck at just the right spot and the system is completely turned to one side so pressure can only come from one side? And maybe when you opened the helm to add fluid it allowed a section of the system with pressure built up to relieve some of that pressure that allowed the air bubble or stuck valve to finally move.

Thanks for the response. I was thinking that as well but what I think might of happened is they didn’t properly cycle the auto pilot when they bled the system. The way I understand it the auto pilot needs to be cycled to properly bleed the lines from the pump to the helm. Could be wrong. As to why it locked out my steering without something like a stuck valve is the air bubble finally got to a spot where it blocked return