STEERING: Hydraulic vs Mechanical Steering for 50ft Trawler

The difference is that my AP was connected to the helm so it had to deal with the wrap-up of that long shaft (pipe) going back to the pitman arm.

It bogels my mind to think the steering loads were so high that you were twisting the pipe , and that caused slop.
Perhaps some end fittings were worn?


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Frankly one regret I have is not having an A/P, and the only downside to fitting to this type of system is the rather heavy price asked for the rotary electric motor and sprocket to link it by chain to the main drive chain, so I could not justify the cost for our boating region and typically not long distances covered. Apart from that, no problem, and the wheel turning with it would not bother anyone.

A vessel with an easy mechanical helm can frequently just fit the cheap tiller ram style AP.

It attaches to the king spoke and will usually only have 4 inches of motion either way , but for sweet boats it is enough,

Try your helm , if tiny few inch corrections will steer , you might borrow a sail boat tiller ram and hook it up to see. About $300 for everything , if it works for you.

makobuilders said:

I'm having discussions with the technical support department of Lecomble & Schmitt for sizing their hydraulic system (manual, not powered). The strange thing is that they comment that if we design the system for 4.4 turns lock to lock, that in their opinion it will be too stiff.

Meanwhile, my last boat (25ft longer, same tonnage, double rudder) had cable steering and was 3.0 turns and I thought it was perfect.

So why would this be, does hydraulic just have that much more frictional losses so that much more effort is required?

Click to expand...

No, it is probably not friction in the hydraulic system itself, but friction in things like rudder post and hydrodynamic loads on rudder. I am not familiar with that brand, but am with other brands and with boat dockside it is easy to turn wheel lock to lock. There is some friction, but there will be in any system.

The turns lock to lock depends on the boat, and can be changed by cylinder bore and helm displacement. Typically between 3 and 6, but there are outliers. Mine is 6.6 which I find annoying while docking, but running at high speed it feels great. If I had to do it again I would go around 4, which is what they are suggesting.

You guys keep talking about mechanical systems, which are fine, but talk about using string and rubber bands for autopilots, or antique autopilots. Fine for coastal short trips, but without a good AP it will wear you out offshore.

If you are going to make passages, you want the absolute best autopilot you can get. Way more options out there for hydraulic AP's.

Offshore, you are on AP almost constantly. Who cares if there is friction in the system!!

Ski wrote re someone else;
"No, it is probably not friction in the hydraulic system itself, but friction in things like rudder post and hydrodynamic loads on rudder. I am not familiar with that brand, but am with other brands and with boat dockside it is easy to turn wheel lock to lock. There is some friction, but there will be in any syst"

When I had push-pull cable steering in my Willard I could steer the boat w one finger. Now it takes two hands and arms. A big part of this is that I've got the Capilano helm pump adjusted to 2.5 turns L to L. I like the fast steering in following seas and in harbor. But the huge increase in steering effort must be in the hydraulic system. And my hose is considerably larger than usual. I took one look at what is usually used for hyd hose on boats and went to a shop that sells diggers and other heavy equipment and bought orange hose that is probably 4 times the ID of the glossy black hose usually used. I was of a mind that was saying larger ID hose would mean less hyd fluid velocity and lower friction and lighter steering.

As I have said before I think the high friction is from the large shafts and seals. Also the larger cylinder piston .. I assume.

However I'm sure it's not form the rudder port, rudder or hydrodynamics of the rudder itself. The steering is just as hard tied to the float.

As to the auto-pilot we had a Simrad on the Albin and assumed we'd miss it in the Willard. But we didn't. At times maybe we'd like to have it back but not often enough to consider it and I almost never go solo.

I need to steer almost constantly when there's swirls and eddys like almost all of Thorne Bay and many other places up north. But most of the time I can .. w about 3 to 5 or 6 adjustments to the helm .. go so straight minutes can pass before another correction or adjustment is needed. It's hard to imagine a short boat w high directional stability but Willy seems to be such a boat.

Probably 9 out of 10 commercial boats including my current personal boat and last one all have hydraulic steering and are steered with one finger or one hand easily. That's over 30 boats.


Most of the hundreds of Sea Rays, Bayliners and trade ins I used to drive had hydraulic steering...they to were almost all easy, palm steering like a car with power steering (which some of the big, twin I/O did have...but none of the inboards that I remember.)Not sure what would make hydraulic steering hard except a mismatch in components.

FF said:

The difference is that my AP was connected to the helm so it had to deal with the wrap-up of that long shaft (pipe) going back to the pitman arm.

It bogels my mind to think the steering loads were so high that you were twisting the pipe , and that caused slop.
Perhaps some end fittings were worn?

Click to expand...

The "shaft" was 3/4" sch-40 galv. pipe almost 20' long. It did wrap-up quite a bit, enough to spin the wheel back 1/4 turn in big following seas. The AP could not be adjusted for this and failed to work properly until I installed the Wagner Hyd. There was no way to replace the pipe with solid shaft w/o tearing the boat apart and that would have had some degree of wrap-up too albeit much less.

"Hydraulic steering" is frequently meant to be the cheapo setup where the wheel turns the rotary pump , and a cylinder or two turn the rudder stock.

That works but gets complex when another hyd system needs to be installed in or over the wheel pump setup.

WE have an entirely different , and quite inexpensive hyd system.

A hyd pump is belted to the engine , the wheel is simply a valve setup that feeds fluid to the twin rams.

The AP powers the system with 2 Vicers hyd electric valves , 1/2 A triggers either.

A Robertson AP that normally has to start a 40A hyd motor has little problem with the 1/2A load.

A bonus with the system is a hyd windlass is added to the system for little cost.

No special cooling circuit is required , the hoses simply lay in bilge water for 20 ft either way , and nothing gets very warm.

Every boat must be thought of as a complete system ,
steering then adding a AP then wiring a DC windlass is the common layer on layer boat assembler method.

Costly and complex.

Thinking it out in advance can save some bucks , as well as make the setup far more reliable.

STEERING - Hydro-Slave Marine

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2001 Hydro-Slave Power Steering. Dia. Class #1 Power Steering single cylinder complete-for 34 ft boats. Extra helm for Class #1. Class #1 w/1.8 turns of wheel.

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I like the shaft thing. It will probably work as well or better than the shift linkage in my 1971 VW bus.

FF: We call that "forklift steering" as all the parts are common to forklifts. And due to that, can be pretty inexpensive. Nothing marine specific about it. Four port helm unit, engine driven pump, whatever cylinder you want on the rudder. True power steering.

I find on some the wheel feel to be quite "vague", but that is subjective.

On one it was tricky getting the AP tuned, and how that was sorted was above my pay grade. But they did get it sorted.