Grand Banks Autopilot help?
 

I'm helping my dear old Dad with his Gand Banks 42'. When he bought it a
couple seasons back, it came equiped with an autopilot that looks like it
hasn't been used in some time & is probably cira 1979 like the boat. It is
not serviceable.

He is looking to replace it with something else. An autopilot for this type
of vessel can be quite expensive. Any ideas on utilizing the actuators
already in place and simply buying the 'brains' of a new one? Another idea
I heard of was using the much more affordable wheel pilots...though this is
complicated by having two steering stations.

Have any of you encountered this type of situation or have any ideas that
might help?

Thanks!

Glenn.
s/v Seawing

Grand Banks Autopilot help?
 

On Tue, 30 Oct 2007 01:59:33 GMT, "Glenn \(s/v Seawing\)"
wrote:

I'm helping my dear old Dad with his Gand Banks 42'. When he bought it a
couple seasons back, it came equiped with an autopilot that looks like it
hasn't been used in some time & is probably cira 1979 like the boat. It is
not serviceable.

He is looking to replace it with something else. An autopilot for this type
of vessel can be quite expensive. Any ideas on utilizing the actuators
already in place and simply buying the 'brains' of a new one? Another idea
I heard of was using the much more affordable wheel pilots...though this is
complicated by having two steering stations.

Have any of you encountered this type of situation or have any ideas that
might help?

Thanks!

Glenn.
s/v Seawing

I assume that you have hydraulic steering so there are check valves in
the system allowing the boat to be steered from either helm so you
could use a wheel pilot.

Again assuming a hydraulic steering system there is normally a
reversible electric driven hydraulic pump that actually moves things
and a "brain box" and fluxgate compass to control the pump. My
experience is that the pump is the most expensive part of the system
and if that is serviceable then a new control head and compass
shouldn't cost too much, probably less then a wheel pilot and for sure
would last longer.

If there are any fishing boats around your part of the country go and
ask them what they are using. I did and ended up using an Australian
made system that you can buy in pieces and assemble what you need.


Bruce-in-Bangkok
(Note:displayed e-mail
address is a spam trap)

Grand Banks Autopilot help?
 

On Tue, 30 Oct 2007 01:59:33 GMT, "Glenn \(s/v Seawing\)"
wrote:

I'm helping my dear old Dad with his Gand Banks 42'. When he bought it a
couple seasons back, it came equiped with an autopilot that looks like it
hasn't been used in some time & is probably cira 1979 like the boat. It is
not serviceable.

He is looking to replace it with something else. An autopilot for this type
of vessel can be quite expensive. Any ideas on utilizing the actuators
already in place and simply buying the 'brains' of a new one? Another idea
I heard of was using the much more affordable wheel pilots...though this is
complicated by having two steering stations.

Have any of you encountered this type of situation or have any ideas that
might help?

I assume you have the usual GB cable steering with the upper and lower
helm ganged together.

Does it have a Wood-Freeman AP with the mechanical chain drive
actuator behind the wheel on the flybridge? That's the way my 1981
GB49 was originally equipped. There are several issues with that unit
including the use of vacuum tubes and mercury wetted relays, all of
which are obsolete and difficult/expensive to obtain.

Prior to my purchase someone replaced the Wood-Freeman with a
Robertson/Simrad AP-35 which is a relatively modern (and modular) AP.
There are various actuators available but mine uses the self contained
electro hydraulic ram connected to a rudder quadrant.

The ram has a clutch which decouples when the AP is off, otherwise
both the upper and lower wheels track the movement of the rudder
quadrant. You can also get a remote control which I use at the lower
helm.

Any similar system that uses a quadrant attached ram should get the
job done much more reliably than the original.

http://www.simrad-yachting.com/Produ...P35-Autopilot/

http://www.wmjmarine.com/sap3519.html

Grand Banks Autopilot help?
 

Several observations:

Don't even think about using one of the wheel pilots. They don't have enough
oomph for a GB 42.

I assume that you have hydraulic steering with a hydraulic pump drive for
the existing autopilot. That pump if still good can be driven by any modern
autopilot. All you need to buy is the "brain" and the control head.

You may have cable steering and I don't know how this is set up for an
autopilot. Perhaps a hydraulic actuator drives the steering gear. A modern
autopilot "brain" should drive the existing actuator just as well.

I have used Raymarine and Simrad autopilots. Both work well. Make sure that
you get one with enough drive capacity. Raymarine has S1, S2 and S3
"brains". The largest can source 40 amps to the hydraulic pump. I suspect
that you will need the largest one.

David