Autopilot Experts - we need your advise

[svrevelations]

We need your help with our autopilot situation.

We have a 50’ catamaran - weight 20,000 Kg. We currently have a Furuno NavNet v2 chartplotter, Furuno radar, Furuno GP32, B&G fluxgate compass, B&G Hydra 2000 and B&G T3 Linear Hydraulic Drive 24V RAM-T3-24V. The T3 hydraulic system is installed on the starboard rudder – the port and starboard rudders are connected with a aluminum tubular crossbeam .

During a recent cross ocean voyage, our autopilot failed and we had to hand steer for almost 2 weeks continuously. Being shorthanded, this was a very tiresome task. It later emerged that the electric motor of the Hydraulic pump seized and now needs replacing.

In view of this experience and the difficulties we had, we now intend installing a second auto pilot system. The second autopilot will be our back up in case the main autopilot system (as above) fails again.

We would prefer not to duplicate all the equipment and we are looking for a bare essentials solution. Something like another B&G T3 Linear Hydraulic Drive 24V RAM-T3-24V installed on the port side – with a kind of switch to select which hydraulic ram we would like to use.

Kindly assist and advise us what is the best solution for our situation.

[Lepke]

You could probably find a replacement motor for the one you've got, or get it rebuilt. The 2nd set doesn't have to be from the same manufacturer as long as it has the same or greater capacity. If it's too big, a restricter goes in the lines.

A second similar setup could be isolated by valves, either manual or electro-hydraulic.

On ships I've been on we have two separate hydraulic systems that drive the rudders. Some use a single level valve that switches one pump set on and the other off while changing the valves. Others used a switch that chooses between the two pump sets and electrically changed the valving.
You should find a local hydraulic shop that can show you the valving and connectors you need. You may need a bigger tank.

[Paul L]

I don't think it is enough to only have a second AP drive. If you want a backup you need a course computer plus rudder position and AP head control. They all have an opportunity to fail and generally a single point of failure disables the system. I setup an all new AP (Furuno AP with L&S hydraulic drive) and then removed the old Raymarine system leaving all the wiring in place. The Ray is wrapped in aluminum foil and stored below as the backup. Hopefully it would survive a lightening strike. It would take me a few hours to reinstall the backup, but that is a lot better than 2 weeks of hand steering.

[noelex 77]

Sorry to hear about your problems.

There are very good reports on the Jefa direct drive units. These high powered electric units have some advantages over the traditional electric/hydraulic drives.

The Raymarine linear drives on our current boat have been excellent with minimal power consumption and heaps of power. I am reluctant to go for the added complication and power consumption of an electric/hydraulic drive.

The larger Jefa DD3 (which is OK for up to a 70 foot yacht) is not much more expensive than smaller Jefa units such as DD2 and if anything is more energy efficient.

Jefa Direct Drive Units

Anyway that is what we have specified for our new boat (a 49 foot monohull), but I stress we have no personal experience, just recommendations from other crusing sailors.

[svrevelations]

Thank you all for your comments and information!

Paul L makes a valid point - whilst our recent issue was the pump, any singular item which breaks will cause the autopilot to fail. Being a computer nerd and not very practical, I did not think that far!

Not very good news financially, but it seems best that we look at a complete secondary autopilot system.

[Neptune's Gear]

The motor - has it really seized? Or just does not work? If it has seized it will almost certainly be bearings. If it just does not go, check the brushes - they wear out, and are a consumable item. Simple to change, and spares should be carried. You can get a spares kit from any Navico dealer, or any auto sparky should be able to make a set up if you're in a remote place. Brushes are cheap.
The B&G hydra 2000 is a pretty old pilot now. If you really want to go down the route of a duplex system, go for a B&G triton system with a precision 9 heading sensor. Solid state, with pitch, roll, and yaw compensation. A HUGE improvement over a fluxgate compass, and a big improvement over the fluxgate rate compass. Use the old unit as a spare.


Sent from my iPad using Cruisers Sailing Forum

[svrevelations]

Originally Posted by Neptune's Gear

The motor - has it really seized? Or just does not work? If it has seized it will almost certainly be bearings. If it just does not go, check the brushes - they wear out, and are a consumable item. Simple to change, and spares should be carried. You can get a spares kit from any Navico dealer, or any auto sparky should be able to make a set up if you're in a remote place. Brushes are cheap.
The B&G hydra 2000 is a pretty old pilot now. If you really want to go down the route of a duplex system, go for a B&G triton system with a precision 9 heading sensor. Solid state, with pitch, roll, and yaw compensation. A HUGE improvement over a fluxgate compass, and a big improvement over the fluxgate rate compass. Use the old unit as a spare.

Sent from my iPad using Cruisers Sailing Forum

Thank you - I will certainly check if it's perhaps the bearings or brushes.

Regarding your Triton suggestion;
I have spoken to two B&G retailers but suspect that they are trying to make more money out of me than necessary. They are hell bent on selling me a complete B&G system with all the trimmings - radar, chart plotter, instruments and many other items. Which basic essential components/equipment would we need for a secondary autopilot system.

[nhschneider]

As we were sailing across the Indian Ocean, we traveled from time to time with a couple on a Wauquiez 48 whose insurance company required them to have a second autopilot installed in a hot stand-by mode. The had chose a different manufacture than their original autopilot but I kind of liked the idea of having two of the exact same autopilots installed simultaneously.

Fair winds and calm seas.

[Manos1955]

Install the same make and model, as a back up system. You can always use the parts in case of failure.

[fabricator-ken]

When crossing the Indian our hydraulic motor stopped working. So I fitted the spare which had allready been rewound previously. I then ordered and waited in Cocos Keeling for it to arrive. Installed it and set off. Two days later pilot failure. This turned out to be rudder indicator. I have also changed the brain en route. It is necessary to carry a complete backup and be very familiar with your hydraulic system .
Happy sailing

[bruce v]

Have you considered wine vane steering as a back up. At least you wouldn't get stuck having to steer or at least be tied to the helm (considering you are doing longer duration open ocean sailing,this seems an obvious back up option). I am also assuming you have an AIS send and receive system that would alert when something is close. On long passages, dozing at the helm is acceptable and, I believe, required - especially if you are short handed. Although the vane is not quite as accurate as a plugged in AP system with all the nuances of today's techno world, it certainly is better than being stuck at the wheel. Fair winds and following seas. Bruce

[svrevelations]

Originally Posted by bruce v

Have you considered wine vane steering as a back up. At least you wouldn't get stuck having to steer or at least be tied to the helm (considering you are doing longer duration open ocean sailing,this seems an obvious back up option). I am also assuming you have an AIS send and receive system that would alert when something is close. On long passages, dozing at the helm is acceptable and, I believe, required - especially if you are short handed. Although the vane is not quite as accurate as a plugged in AP system with all the nuances of today's techno world, it certainly is better than being stuck at the wheel. Fair winds and following seas. Bruce

Yes, I had a look at a wind vane system which can be fitted to a catamaran. Maybe it's all in my mind, but it does not look right. For now, I am more interested looking at a plugged in system.

[Mainstay]

I have basically the same requirements for my Venezia 42. Currently I am looking at installing something like this:

Linear Drive for Raymarine Simrad Autopilots | eBay

[Blue Stocking]

[QUOTE=Mainstay;2147958]I have basically the same requirements for my Venezia 42. Currently I am looking at installing something like this:

Linear Drive for Raymarine Simrad Autopilots | eBay[/QUOT

That looks like a good price. Pump capacity is capable of delivering the " hard over-to-hard over" times you will need ?

[bruce v]

Originally Posted by Revelations

Yes, I had a look at a wind vane system which can be fitted to a catamaran. Maybe it's all in my mind, but it does not look right. For now, I am more interested looking at a plugged in system.

You are right. It's all in your head. Find out how it works (if you take a few pics and post your questions here, some will certainly be able to instruct you on how to set it up and use it. You might also look for detail on type, quality and capacity. Not too hard and if you already have it, why not. Worst case scenario, it doesn't pass muster and then it becomes excess bagge you can get rid of.