confused about auto pilots

[bigsarg1]

I have an Irwin 1978 37 center cockpit. I am considering a wheel pilot, which I know is slightly underrated for my boat. I have seen the raymarine ST4000 for sale on ebay a number of times for a reasonable used price. I understand it is rated for a sailboat w/ a displacement of 18,000lbs. and no more than 20,000 lbs. The Mk II wheel-drive can be purchased to improve the ST4000. Then came the S1 w/ the Mk II wheel-drive which is the successor to the popular ST4000, but is rated at 16,500lbs displacement. Now the new X-5 Wheel autopilot which is also rated for 16500. Well, why did the displacement drop. If the Mk II wheel-drive can be used w/ the ST4000 then theoretically the S1 and X5 can handle the same displacement. Am I correct in my thinking or am I way off?

[capn_dave]

You can never be sure about anything with Ray Marine.
That I'm sure of.

Dave

[brak]

possibly because these wheel pilots never worked very well for heavy displacement boats and RayMarine decided wisely to reduce the rating. This way they get less complaints from owners that decided to buy cheapest possible system for their boat, and at the same time get to sell more expensive systems instead Win-win for them.

Seriously, though - wheel pilot systems cost about as much as linear drive, and a cost of building a hydraulic system is higher but certainly not so much to make it prohibitive. The result would be far better with either of the latter.

[Omatako]

I had an ST4000 wheel pilot on one of my earlier boats that was 36 ft and weighed in at 7800kgs (17000lbs approx)

It was rubbish on that boat which sounds basically similar to yours

Nufsed.

[bigsarg1]

A friend has the same boat as I, and has the ST4000. It has worked remarkable well for him. My sailing is coastal and if the weather turns I would be at the helm. I just can not find myself turning over my life and equipment to a computer. I mainly need it for raising and lowering the sails and when I need a break from the helm. I have talked to many sailers that tell me the life span of a under the deck autopilot is only around 5 yrs. So, I would whether just have a simple wheel pilot that I can replace every three years or so and come out better financially. Am I way off in my thinking?

[Faster]

Originally Posted by bigsarg1

...... I mainly need it for raising and lowering the sails and when I need a break from the helm. .....

Under those operating conditions I'd think the wheel pilot would do just fine. Even on our 11,500# boat, I'm not impressed with our S-1's behaviour when powered up under sail - thankfully it doesn't steer near as well as I can.
So we use ours much as you plan to use yours.. setting and dousing sails and long chugs in calm seas.

[brak]

It's true - everything depends on use. I practically never steer - hydraulic steering is best left to professionals .

On a few offshore crossings (caribbean mostly, not on my boat, though) I found autopilot to be a much better helmsman. In somewhat significant gale conditions (waves of 10-15 feet) where human helmsman was exhausted in minutes trying to keep the boat even relatively on course, the mechanical one worked day and night, non-stop keeping course as well as I never could even in better conditions.

[bigsarg1]

The only thing about a under the deck pilot that I like: is another way to steer the boat, if my steering is broken. But, the price and the way I will be using it. I think the cheaper wheel pilot is just the best thing for me. I do not try and sail in bad weather. And, being retired I can just about avoid it. But, the optional steering is a plus. Then again, I have BoatUS unlimited towing. lol.