Question: I am planning a long trip in June (Sardinia to Canaries) and then the ARC in November. A working autopilot would be nice. I’m looking at Simrad autopilots. What drive would you recommend for a Swan 44 (displaces about 30,000lbs)?
Answer: Your Swan is a big powerful boat and you are planning a downwind trip in big trade wind seas that will challenge your autopilot. (Autopilots are much more heavily stressed downwind than going to windward.) So I would recommend putting some time, effort and money into a really bomb proof installation of the new drive.
Here are some thoughts to keep in mind when selecting a drive:
- I think that, in general, hydraulic drives are more reliable than electrical (that is, an electric hydraulic pump driving an hydraulic cylinder).
- When selecting the pump/cylinder set, go big. I think autopilot companies often underestimate the loads on a voyaging sailboat.
- Simrad sometimes specifies two rams to get the power they need on bigger boats. Except for the largest boats, I don’t like this approach since it adds another level of complexity and more seals and hoses to leak and blow. If Simrad’s ram is not big enough for your boat, have a look at those from Hynautic, used with a Simrad pump. This is what we use and it has worked well.
- Make sure that you, or whoever is installing the drive, uses the correct sealants properly applied on all hydraulic joints. It is amazing to me how many experienced technicians that should know better will use ordinary pipe dope on the joints. This is the reason that many users of hydraulic autopilot drives complain of leaks.
- The mounting points for the ram must be truly massive to take the load and there must be NO play or slackness anywhere. Here is a test: After installation, engage the autopilot and then have someone try to turn the wheel back and forth against the ram using the same amount of force as you would steering in big seas broad reaching. While they are doing that, look at the complete installation. If there is ANY play, flexing, or other movement, it is not strong enough. By the way, if the boat’s steering can’t stand this test, it should be beefed up too.You may wish to have a look at autopilots from W-H. We have a Simrad and are very happy with it but I have heard good things about W-H.
Eva June 28, 2012 at 8:40 am
Hello,
Have you ever considered the electric direct drive units from the Danish manufacturer Jefa as a replacement for hydraulic drives? The advantages are its frugality as it uses electricity only when moving the rudder and the low level of friction it adds to the steering system when steering manually.
I recently installed the Jefa direct drive type 1 unit on my Able 34 cutter, but I have only used it for a couple of overnight sails yet.
This far I’m happy, it does what it’s supposed to do with no complaints and you only hear it when it corrects the course. I compensated the friction the direct drive unit added to my steering system by increasing the diameter of the steering wheel by an inch or so.
http://www.jefa.com/steering/products/drives/drive.htm
http://www.jefa.com/steering/products/drives/direct-drive-menu.htm
John June 28, 2012 at 3:23 pm
Hi Eva,
Thanks for the comment and suggestion. No I have not considered the Jefa drives, but I have heard good things. I would certainly look at them if we were considering changing our drive. However, our present drive has worked flawlessly for some 40,000 miles, all the parts are still made, and we have 100% backups. So, if its not broken, don’t fix it, will apply here.
Just to clarify, our hydraulic drive only uses electricity or makes noise when it is actually makes a steering adjustment. There are hydraulic drives that have motors that run continuously, but they are rare on sailboats.