[C320-list] EV-100 install on early 320

[Stephen Cox]

> 
> I am currently awaiting an EV - 100 Wheel Steer system that 
> is on back order which I plan to install on a 2007 C320 MK II 
> and are wondering if anyone has comments on any difficulties 
> mounting the Wheel unit on the square Edison pedestal that 
> the later C320's have. 
> 
> In particular, comments on drilling the pedestal to 
> accommodate the motor of the system as the pedestal appears 
> to be to wide to have the motor pass down the side of the 
> square pedestal.  
> 
> I am also interested to know if there was any difficulty 
> accommodating the autopilot wiring in the wiring conduit 
> inside the pedestal.
> 

I have installed an ST4000 MK II wheelpilot in the C320 MK II Edson stand.  From memory, on the rear face of the stand, left of the
centre line and within the arc of the wheel, there is a dimple which indicates the appropriate place to drill for the motor
assembly.  Also can't remember if it came with the kit or it was an extra but there is a rubber gasket and metal ring that seals the
motor mounted into the stand.  In my case the motor and cable extended well back into the stand and I had to remove part of the
internal port side cable ducting to give the cable a clean path.

I mounted my system controller in the master cabin on the rear bulkhead, above the mattress and between the access door and the
fibreglass steering mechanism cover.  This has the advantage that it is kept dry, is easy to access to check the fuses, is
reasonably close to the centre line of the yacht which is recommended in the installation instructions and can be wired through the
bulkhead so no cable extensions are required.


In practice, I found the wheelpilot to be an altogether inadequate piece of gear.  The gear train in the motor is not robust, the
lever as others have said won't hold in in heavy weather.  Belt tension adjustment is problematic at best.  For smooth water sailing
it works fine but that is a luxury I don't have.  In my experience in stronger weather with significant swells and 20 - 30 knot
winds it just doesn't cut it.  I have experienced gear teeth breakages and damage to the backing ring which made belt tension
adjustment problematic.  For me the wheel pilot lasted most of one significant offshore trip, from the Australian NSW coast across
Bass Straight, around Tasmania and return.  I replaced the gear box once and rebuilt it a further twice salvaging gears out of the
first gearbox as required.  We made it back across Bass Straight but with considerable belt slippage.  The trip back up the NSW
coast was all hand steered as the wheelpilot was pretty useless by then.  

I have now fitted a hydraulic ram drive driving a tiller arm/lever affixed to the rudder stock.  I used a Jefa tiller arm which is
machined aluminium and was also cheaper than the Edson cast arm.  Given potential shock loads on a rudder I am not convinced that
using a cast arm is desirable.  To ensure the grip onto the stock I drilled and tapped a suitable hole into the rudder stock for a
bolt rather than relying on grub screws or just clamping alone.

Stephen Cox
Tegwen #1141