Autopilot drive - repair or replace?

Chrick

New member
20
24
Chester, NS
My new-to-me J/44 came with a Navico NAC-3 autopilot brain and a Simrad/Robertson HLD2000 MKII hydraulic linear drive (actually two, no idea of the state of the spare other than it's not new). The drive leaks enough that I've had to fill it twice, but works pretty well when it hasn't lost it's fluid. The drive units aren't made anymore, Simrad has a replacement part, but it's a different unit - parts aren't available unless they're new old stock for the Robertson (as far as I can tell through internet searches).

Autopilot is very important to me - it makes it possible to singlehand the boat, and makes it possible to do longer trips in relative comfort. When the drive stops working because it needs oil things just don't run as smoothly, even when there are two of us.

So - given that I want a reliable system, would you recommend finding a place to fix up the two drives I have, or starting from scratch with something newer?

All advice welcome and appreciated!

Thanks,

Chris
 

slug zitski

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Hard to say

A set of hydraulic oil seals is cheap …those seals are not proprietary , they are common size seals

pumps , valves and motors can be a bit tricky to source ..an autopilot guy will know

is it worth repairing ?

if your duty cycle is offshore buy new stuff

if you are a local cruiser…. service the gear and hope for the best

the common failure point on the motor are its brushes and the brush holders

auto pilots don’t like low voltage …clean connections, proper wire size and a low voltage alarm
 

longy

Overlord of Anarchy
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San Diego
If the ram seals are leaking, any good hyd shop can replace them. Test fir to determine if the 'spare' ram fits on existing mounts/brackets. If it can be immediately swapped in, then get it tested/repaired. As you have found, as long as you can refill the hyd reservoir, leaking seals do not knock out the drive unit. I'd carry oil before I'd carry a full spare hyd auto ram. The electric pump is a single point failure, however - but I've never had that happen.
 

longy

Overlord of Anarchy
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San Diego
You might want to research the spec's on the 2 units you have. Faster response & lower amp draws are good things (usually mutually exclusive) and check that stroke lengths are identical. It is death to a cylinder if the cylinder is the rudder stop, so make certain your stop is within the ram stroke.
 

slug zitski

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If you decide to go with a new drive unit eliminate the hydraulics ….they are slow , power hungry , complicated , inefficient ….

choose a servo motor driven linear drive

Jefa is the best in the business

your boat is at the top of the size range , contact Jefa for suitability and options



BF4D8B7A-6C93-47D4-927B-2B1989E1277E.png
 

Chrick

New member
20
24
Chester, NS
Thanks for the good advice. My first thought was exactly what longy suggested - fix the spare, swap, fix the original, carry on with comfort. After reading another thread on autopilots here, though, I read that electro-mechanical is maybe better than hydraulic, which made me wonder if a switch was worth it.

Does anyone have an opinion about Raymarine’s linear drive? I had one of those on a previous boat and it was always effective - but I only owned the boat for five or so years after installing it, so long term I have no real idea. Our local chandlery (binnacle.com) carries them, making it an easy choice. Of course it’s always possible to get something else, just less convenient!

I think this fall/winter I’ll do the repair on at least one of my existing drives, and plan on a new route before doing any more extensive cruising - at this point I’m getting a three week coastal cruise in NS annually - it’s rugged enough offshore that I want reliability, but not like I’m cruising full-time in remote locations.

Thanks again!
 

ryley

Super Anarchist
5,509
665
Boston, MA
Does anyone have an opinion about Raymarine’s linear drive?
I've got a Raymarine Type 2 on my Freedom 45. It's been reliable - I did have to replace it 2 years ago, but at that point the original (Autohelm) which had never been upgraded from the nylon gears finally gave up the ghost and rebuilding it was going to cost only a little less than a new unit. I had no problem with it driving to Bermuda and back last year. It appears you should be able to integrate a type 2 with the NAC-3 although Simrad could probably give you a better idea.
 

WHK

Super Anarchist
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Newport, RI
I've got a Raymarine Type 2 on my Freedom 45. It's been reliable - I did have to replace it 2 years ago, but at that point the original (Autohelm) which had never been upgraded from the nylon gears finally gave up the ghost and rebuilding it was going to cost only a little less than a new unit. I had no problem with it driving to Bermuda and back last year. It appears you should be able to integrate a type 2 with the NAC-3 although Simrad could probably give you a better idea.
I can confirm this works. I retrofitted a friends J/122 that had a Raymarine pilot with the Type 2 drive. It still has the Type 2 drive and now has an NAC-3 with Zeus 3 and Triton 2 pilot control on the sprayhood.
 

longy

Overlord of Anarchy
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San Diego
How often/hard are you going to use the auto? The Ray linear drives are OK, low amp draw, very low added drag to steering feel, but do have catastrophic failure mode & plastic internals. Hyd drives are more powerful, do draw more amps, usually very long lived. The Jefa frives may incorporate the best of both, I have no direct knowledge of their use.
 

ryley

Super Anarchist
5,509
665
Boston, MA
How often/hard are you going to use the auto? The Ray linear drives are OK, low amp draw, very low added drag to steering feel, but do have catastrophic failure mode & plastic internals. Hyd drives are more powerful, do draw more amps, usually very long lived. The Jefa frives may incorporate the best of both, I have no direct knowledge of their use.
this is no longer true. they did, and offered an upgrade to bronze, but I believe they are all built with bronze now. Even so, as I said my nylon gears lasted for over 20 years.

FWIW, I have yet to run into an autopilot failure that *wasn't* catastrophic in some way, whether it was the arm or the brains that failed.
 

slug zitski

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this is no longer true. they did, and offered an upgrade to bronze, but I believe they are all built with bronze now. Even so, as I said my nylon gears lasted for over 20 years.

FWIW, I have yet to run into an autopilot failure that *wasn't* catastrophic in some way, whether it was the arm or the brains that failed.
Typical failures are the clutch or dc motor brushes

good idea to have spare set of brushes and inspect , clean the contact surface from time to time

those plastic wheels seem to last a long time ..Ive never had them fail
 

SimonGH

Member
410
88
Westbrook CT
Seems like you just need to get the seals repaired (if that's where it's leaking from?)

Are they the "all in one" version or the "split" version with hoses?

Can you actually tell where it's losing oil? Is it from a hose connection or the piston seal itself?

If it works sufficiently otherwise, then fix the leak.

You say you have a "spare". Perhaps when you remove the leaking one for repair, put the other one in and see if it works?

Seems to me if you don't find something that is an exact fit and match to the existing setup, then you're into a project with mounts, rudder arms, position sensors, etc. It's a boat project - nothing is easy.

If I had the same situation you have then I'd want to fix the leak and figure out the status of the spare. Ultimately you'll end up with two working drives and thus better overall redundancy than one new one. (I'm assuming these units are pretty reliable). Take it to a hydraulics shop, they deal with this type of issue all the time.
 

Chrick

New member
20
24
Chester, NS
I use the autopilot constantly when cruising, which is 3-4 weeks/year at this point. When racing it sits idle, that's the rest of the season (short season here in NS). As far as how hard - depends on what the wind and sea state are doing. Coming up the coast from Chester to St. Peters a couple of weeks ago we were nearly DDW with 30 knots pushing us along, hitting up to 14 knots down waves - at that point it was working pretty hard! That's not the normal use case, though - normally the boat is pretty well balanced and we're sailing along reasonably easily. I'd like to cover both cases, of course.

The Jefa unit does look pretty great - but I agree that if it isn't a direct match for bolt pattern and length it'll be a project to install. The factory (I believe) installed a glass pedestal in the lazarette with captive nuts for the bolts that secure the Robertson drives - direct match seems unlikely, but maybe? They are the unified drives, by the way - reservoir and pump all on the same unit with the piston. Leaking is from more than one place, I believe - it's coming out on the piston end toward the rudder post, but there is also fluid on the pedestal, meaning it's also coming out the other end, or from the central unit itself. I have bench tested the spare, it seems to work, but I don't think it would leak without being put under some stress - I'll wait until I'm in home waters to test it out so that I'm limited in how long I'll be hand steering if I'm disappointed.

Given this winter likely also has a roller furling replacement (anyone with opinions on the Harken Mk3 Unit 2 they'd care to share? I have a couple of issues that can be worked around but it's a nuisance, and they've stopped making parts after a mere 30 years), I'll likely take the less expensive route and see if the Robertsons can't be made reliable and put the Jefa or Raymarine on the want list for another year.

Never-ending want list!
 

slug zitski

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Modern autopilots are very reliable when operated in thier comfort zone

14 knots in a 44 footer is not in the comfort zone

under autopilot , when the boat starts moving over speed, i slow down or drive by hand
 

Wright Way

Member
426
213

We are going through same drama with Navico LA2 version,
These guys are the manufactures of the original navico units, the current model looks like a drop in solution, or near enough to.
 

badia420

Member
128
64
Barcelona
I just replaced my ram with a Hypro, directly from the dealer, not through BnG, and it is affordable and for the moment working good in my "customJ120ish" cruiser-racer
 

Sunny1925

New member
10
0
Marblehead
My autopilot was new in 2017 it's a raymarine wheel mount and it doesn't hold for more than a few min in anything but very light air. Boat is 36ft and a couple people have told me it's too big for wheel mount - but it's well within wt range according to raymarine website. Should I just be expecting to need to get a new autopilot at this point, 6y out? I really want to be able to take a nap on long hauls, and not get thrown off the bow when it fails. Have tightened the clutch a bunch of times but any improvement is short-lived. I think it's been recalibrated but not sure the guy could get to it. B&G sounds way $$$ and hard to get fixed, and all my stuff is raymarine. I guess will talk to dealer but any insight appreciated thanks
 

longy

Overlord of Anarchy
6,768
1,127
San Diego
Wheelpilots suck - always have & always will. Throw it away now. Since you already have Ray gear, get a Ray pilot so it can talk to other stuff. Underdeck is most expensive - but most reliable/easy to use installation.
 




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