sprocket and chain hydraulic steering

[gails]

Hi,
desperate for some advice. We are refitting our ketch and the manager has developed this steering idea and built a pedestal to fit.

The idea is that a sprocket and chain runs from the wheel inside the pedestal to the hydraulic pump at the cockpit floor and then the hydraulic steering system begins.

Has anyone heard of this before? I know it is on the other boat he refitted and appears to be working.

The next question is the size of sprocket and chain. Edson state that they don't make sprockets and chains to match a hydraulic steering system. This means we are stuck trying to work out what we need… the other boat has not kept records.

ANy ideas out there.

[Auzzee]

I have had such a system previously. It was a HyDrive unit in a centre cockpit. Pump was above the engine and bolted to the cockpit sole. The sprocket behind the wheel was the same size as the one on the spindle of the pump. A stainless chain connected the two.

The system was the recommended, standard installation by HyDrive. Have a look here. Open the link and scroll down to page 19, Installing the Helm Pump Below The Pedestal:

http://www.hydrive.com.au/site/images/HDAdmiral.pdf

[delatbabel]

This sounds like one too many moving parts for my liking. If your steering stops working (and it will), where do you look first? Chain? Sprockets? Hydraulics?

The other thing that bothers me a little is the combination of chain/sprocket grease and hydraulic fluid. The two should not be allowed to mix.

[Auzzee]

With respect, there is no possibility that the two lubricants can come to mix. The only extra moving part is a heavy duty stainless steel chain and a separate bearing which will add a degree of protection to the pump innards and seals which will lengthen the life of the both the pump and seals.

There is no practical, additional avenue for breakdown yet there is positive extra protection against breakdown.

[HandyBilly]

Interesting idea to do this with chain and sproket. You could convert an existing helm station to hydraulic more easily. I guess that was the point of the original post by Gails. Did you do it yet, Gails or do something different?