Advice on autopilot for small wheel steered hydralic rudder and large outboard engine

[Grith]

Hi All I am continuing the development of an unusual trailable yacht for extended inshore exploration and live aboard cruising.
The usual tiller pilots most of my fellow cruising trailer sailer owners fit are unsuitable to my yacht which has hydraulic wheel steering for both its rudders and oversized outboard with lever activated switch between both steering modes.
As I live in a slightly remote area it’s difficult to find a marine store or expert in the area whilst I can order and have delivered from online.
Due to depth constraints in the area here the local yacht clubs don’t have many deeper keel larger cruisers where the appropriate auto steering systems are more common.
My wheel and binnacle are relatively small as is the cockpit size ( as shown below) but I have a good supply of battery power.
My new sailing partner whilst wonderfully keen and supportive of our goals to spend significant time onboard cruising/exploring coastal and inland remote waters is a complete novice having previously never even set foot on board a boat prior to our meeting.
( 6 weeks living onboard with her already tested for you fellow cranky skeptics )
Whilst Clare can already manage to steer for short periods I would like to be able to move around the yacht leaving the helm to the autopilot for more extended periods for both longer passages and occasional solo sailing.
Can some knowledgeable people here give me some recommendations for appropriate systems?

[stormalong]

Do you have room on your rudder post for a separate tiller arm and an autopilot drive? That would be my suggestion. Makes for a robust autopilot independent of your hydraulic steering.

[deblen]

I don't understand that you have a normal hydraulic steering system that controls twin rudders-plus you have some kind of other steering that controls an outboard motor.
And you can switch between the 2 systems with a ?switch?.





Here is the plumbing for a normal hydraulic steering system with an optional electric,reversing motor pump. The electric pump is controlled by the +/- output of the autopilot without turning the steering wheel.
An additional option would be to have a jog switch to also control the electric pump for manual steering.

[deblen]

pump.jpg Views: 53 Size: 50.4 KB ID: 268025" style="margin: 2px" />


https://www.projectk.co.jp/marine/pdf/CAPILANO1250V.pdf

[Baby tug]

Originally Posted by deblen

Attachment 268025


https://www.projectk.co.jp/marine/pdf/CAPILANO1250V.pdf

Now get rid of the helm pump and get what is called a follow up jog lever and a ruder indicator

[goboatingnow]

Originally Posted by Baby tug

Now get rid of the helm pump and get what is called a follow up jog lever and a ruder indicator

Well if you have an AP. You can typicalkybpower steer via it

[Grith]

Originally Posted by stormalong

Do you have room on your rudder post for a separate tiller arm and an autopilot drive? That would be my suggestion. Makes for a robust autopilot independent of your hydraulic steering.

Hi No unfortunately there is no rudder post as the two rudders are stern hung and activated by a hydraulic ram.

[Grith]

Originally Posted by deblen

I don't understand that you have a normal hydraulic steering system that controls twin rudders-plus you have some kind of other steering that controls an outboard motor.
And you can switch between the 2 systems with a ?switch?.


Attachment 268024


Here is the plumbing for a normal hydraulic steering system with an optional electric,reversing motor pump. The electric pump is controlled by the +/- output of the autopilot without turning the steering wheel.
An additional option would be to have a jog switch to also control the electric pump for manual steering.

Thanks but yes the stern hung twin rudders have a manual valve that cuts their off and activates another ram on the outboard.

[Pete7]

This is all sounding rather complicated, why not simplify it? Remove the bit that steers the outboard. Add a hydraulic pump to the existing steering system and drive it with something like this, but purchased locally:

https://hudsonmarine.co.uk/products/...d-p70rs-t70154

One of the problems with hydraulic steering systems which I had, is creep. Very slowly the wheel would need to be turned one way due to the torque on the stern drive. Therefore, a wheel or electric drive couldn't be fitted as the direct ahead position of the drive, or in your case the rudders and the wheel was ever so slightly changing. It was only really noticeable when steering in a straight line for many miles.

So the solution is a pump in the hydraulic system and probably a rudder reference unit so the AP knows what the rudders are actually doing. Adding this made a huge improvement to a drag link AP system from Raymarine.

I don't think a tiller pilot isn't going to have the power to turn the steering if a hydraulic ram is connected to it.

[Grith]

Yes I have noticed the creep moving back and forward between the two hydraulic ram systems for the rudders and engine.
The current system works very well with just the push of a lever to swap rams and I am reluctant to change this.
Also being a trailable yacht with the ram systems mounted under a lift up additional swim platform level which covers all the mechanicals with tight clearances I think best to leave all this alone.
I have a neat little gadget stuck to the middle of the wheel to indicate when the steering is straight ahead which I have mounted to the push in timber wheel centre which I can still manually friction adjust to compensate for this movement to keep it indicating the correct wheel to rudder/outboard alignment.
The creep you mention is one of the issues I know will effect installation and effective use of an auto pilot.

[Jammer]

Why is this hard? There are hydraulic autopilot drives available from all major vendors. Am I missing something?:


Raymarine has four, different sizes: https://www.raymarine.com/autopilot/drive-unit/


https://www.garmin.com/en-US/p/878046


https://www.lowrance.com/lowrance/ty...ydraulic-pack/


I believe they will all work without a rudder reference though they may bottom out the ram occasionally.


Two of the drawbacks with hydraulic autopilots are cost and power consumption, but those are tradeoffs you'll have to live with given the way you have your steering set up.

[wholybee]

Originally Posted by Grith

Yes I have noticed the creep moving back and forward between the two hydraulic ram systems for the rudders and engine.
The current system works very well with just the push of a lever to swap rams and I am reluctant to change this.
Also being a trailable yacht with the ram systems mounted under a lift up additional swim platform level which covers all the mechanicals with tight clearances I think best to leave all this alone.
I have a neat little gadget stuck to the middle of the wheel to indicate when the steering is straight ahead which I have mounted to the push in timber wheel centre which I can still manually friction adjust to compensate for this movement to keep it indicating the correct wheel to rudder/outboard alignment.
The creep you mention is one of the issues I know will effect installation and effective use of an auto pilot.

I would expect that creep won't be an issue if you install an AP with a rudder position sender. With that, the AP will follow the rudder, and not care where the motors are. Even the cheap wheel attached unit should work perfectly fine *if* you buy the extra rudder position sender. The hydraulic is preferred, though.