Loss of steering at the lower helm

[Sadey]

Went to use Benedetto the other day and had no steering at the pilot house helm. Fly bridge worked as advertised as well as the A/P. It’s hard to tell the fluid level in the reservoir but it might be low. There is less then 10psi on the gauge so there’s that as well. What’s weird is, no extra fluid visible were it shouldn’t be and why is the upper helm working instead of visa versa?

Side note: while I was cleaning the upper helm I must have bumped the A/P on. Took me a while to realize the noise I thought was somebody else’s boat was actually my A/P pump working away. Obviously I turned it off until we needed it enroute. All this shortly before I discovered the complete lack of steering south.

Thoughts besides add fluid and pressure?

 

[Pascal]

You can try but typically if the system is low on fluid or air, the upper helm is the first one to go.

Top it off and then bleed both helms by turning until you get a stop then the other way till opposite lock.

 

[SEVEN]

PSI should be 25 lbs.

 

[eze2bme]

Did you check for fluid leak at the AP ram?

 

[Sadey]

I didn't think to check the ram because the auto pilot was working properly.

 

[Freeebird]

Wouldn’t think a ram leak would affect only the lower station. As we discussed, I’ve lost steering from top to bottom via a near ram leak, and the AP was the only thing that halfway worked toward the end. I’m no expert, but losing that lower station and still having the upper baffles me. I’ll be looking forward to seeing what turns out to be the culprit.

 

[oscarvan]

Wouldn’t think a ram leak would affect only the lower station. As we discussed, I’ve lost steering from top to bottom via a near ram leak, and the AP was the only thing that halfway worked toward the end. I’m no expert, but losing that lower station and still having the upper baffles me. I’ll be looking forward to seeing what turns out to be the culprit.

Not familiar with the innards, but Hynautic lists a bunch of seal kits for the help pumps..... wouldn't it just be a spinner if they fail?

Does the autopilot generally have it's own ram on the rudder mechanism? It did on my last boat which provided much needed redundancy. Or is it just another pump in line on the main system? Less redundancy......

 

[Pascal]

As I mentioned earlier, low fluid always affect things from the highest point. I once had a fluid cooler failure on a power steering hynautic while returning from BIM on AP. Fluid was being dumped over board . When I disengaged the AP to make the turn into Cale Florida... at 24kts... the wheel just spun and spun and spun. Quickly re engaged the AP which worked fine for a few more minutes letting me make the turn then center the rudder and finished the trip across the bay steering with engines.

Sounds to me like a bad helm pump

 

[Freeebird]

As I mentioned earlier, low fluid always affect things from the highest point.

I think Sadey mentioned it first.

 

[jmooney]

I am in the process of rebuilding my helm pumps and steering cylinder. Also replacing the flexible hydraulic hoses. The Hynautic manual does not specifically mention this situation in the trouble shooting section, but it refers to a helm that keeps turning without stopping as have too much air in the helm pump. You probably need to make sure that sufficient hydraulic fluid is in the reservoir and proper charge is obtained (20-30 psi) and then bleed the system , starting with the highest helm.
Hope that a simple fix is in the works. Jim

 

[sixty]

If there is still some pressure and fluid in the reservoir there is no way air could be introduced into the system, hence the pressurized reservoir. It is possible that some air may have been trapped in the system and air locked the helm but this doesn't seem that feasible if the system was working fine before the failure. I have never seen the inner workings of a helm but assume they rely on seals to move the fluid at pressure and would guess these seals failed.

 

[Sadey]

It’s killing me to have to wait until next week to implement these suggestions. I wonder if the AP pump trying to steer for the time it did has anything to do with it.
What’s turned me white as a ghost is I never thought of the possibility of loosing all steering as a result. First time with a dual helm boat and still very green on this boat. I know how to steer with the trannys but oh boy what baptism that would have been. Winds were blowing hard out on the ICW.

 

[racclarkson@gmail.com]

It’s killing me to have to wait until next week to implement these suggestions. I wonder if the AP pump trying to steer for the time it did has anything to do with it. What’s turned me white as a ghost is I never thought of the possibility of loosing all steering as a result. First time with a dual helm boat and still very green on this boat. I know how to steer with the trannys but oh boy what baptism that would have been. Winds were blowing hard out on the ICW.

Far from the worse calamity that will befall you. You adjust pretty quickly. Easiest if you can center the rudder with AP and power steer. AP probably had nothing to do with it. After verifying fluid, pump it up to 30 and work the wheel. Then work the upper in case you passed an embolism upward.

 

[Freeebird]

The AP thing seems odd. You have to turn on the power, then press another button to engage it. Then it’s just going to maintain the present rudder position and not let you turn the wheel (with any effect) until you disengage it.

 

[oscarvan]

in case you passed an embolism upward.

Good technical term. I like it.

 

[Sadey]

Ah yes the chain of events. I had the panel that the AP pump is on for another reason. I also had the electronics on which include the AP control head for a nav software update. I can’t imagine what the pump was working against tied to the dock but it was working away. That’s how I figured out what the noise was. I noticed “heading hold” on the control head. Again not sure if it’s related but it’s the only steering related thing that took place between our last docking and this event.

 

[Pascal]

Depends on the AP. Most modern AP will disconnect and stop trying to turn the rudders off the boat doesn’t respond. For instance with Simrads if you stop and start drifting with the AP left on, the AP will see the heading isn’t changing and disengage with a “Rudder Response Failure” Alarm.

Personally I don’t see how the AP pump could have affected the lower helm but I ve seen stranger things

 

[Freeebird]

Good technical term. I like it.

I like helm fart better.

 

[racclarkson@gmail.com]

Depends on the AP. Most modern AP will disconnect and stop trying to turn the rudders off the boat doesn’t respond. For instance with Simrads if you stop and start drifting with the AP left on, the AP will see the heading isn’t changing and disengage with a “Rudder Response Failure” Alarm. Personally I don’t see how the AP pump could have affected the lower helm but I ve seen stranger things

Not exactly. Tied to the dock, the AP will work all day long correcting for that 2 or 3 degree bounce against genders and lines.

 

[SKYCHENEY]

Not sure I understand when the lower helm failed, but with the old Robertson the pump will run continuously once its turned on. And if the AP was engaged, you will get no response from the helm. So I'm assuming you tried the helm once you turned off the AP and it still doesn't respond? If so, I agree that it may be a helm pump issue as there is still oil and pressure in the system.