Autopilot drive replacement Lewmar to Jefa

[SYJetzt]

I´m currently outfitting my boat for long distance hauls.
As I'm sailing shorthanded, I'm thinking about my spares for the autopilot system (drive).
Actually i have a Lewmar Mamba (12V 1/4HP) which works fine (at the moment!), but i have read all the issues in other threads about clutch problems.
A complete drive set (motor, gear, clutch) from Lewmar is about 3100.-€.
Jefa offers a complete drive unit (including a flange-adapter) for about 2000.-€, where the clutch seems to be of another construction type (bolts instead of friction plate).
I'm aware of the issues with the jefa rudder feedback sensor, but my current drive has an extra rudder sensor, so i don't need the jefa sensor.
Are there any known issues with the jefa drive (exept the rudder sensors?), i think all newer bavarias from 2015 on should have one!

[SofiaB]

2016 Vision 46; no issues so far.  I sail solo and use the autopilot a lot.  As you mentioned the internal rudder sensor (pot) was a nightmare but once I switched to the Garmin GRF 10 rudder sensor, I've had no issues thus far.  Both Jefa and Garmin recommended the replacement to the external sensor and I finally caved after replacing the pot 3 times.  With the Jefa autopilot, you do have to wait for the clutch to disengage before turning the wheel which is somewhat scary when a power boat turns directly into your path.  If you don't wait and fight it, it will not disengage and you will not be able to turn.  The clutch must hold the magnetic charge for a brief time before it disengages.  If you wait and don't fight it, it disengages with no issues.  This is just something you have to get used to and typical of any magnetic clutch system.  The Garmin autopilot system settings is also something that I've had to get used to.  The weather changes quickly where I sail and there are some changes with power and response time that must be tweaked for the autopilot to perform well.  For instance, in light winds the most economical settings and lowest response time works well and wheel hardly moves.  In over 30 knots, the response time is maxed out and normal econ mode is required. Also, different sail plans require different settings.  It took an entire season to tweak the settings for a new asymmetrical.  Also, factory settings was actually disabling the autopilot in higher winds but I finally discovered how to disable that feature so I can now set autopilot in any weather conditions.  But, higher winds are typically short lived on the Great Lakes so power usage is not normally an issue.  Overall, I'm happy with the Jefa / Garmin system but after 4 seasons and trips lasting up to 6 weeks I'm still getting used to it and continuing to find the best settings.  One major improvement would be to have the settings stored as a recipe so I could simply recall the settings based on sail plan and weather/sea conditions.  Maybe Garmin will see this and make a firmware change?! 

[SYJetzt]

Thank you for the detailed info!
How long does it take to disengage the clutch from auto to hand steering and release the rudder wheel (estimate)? If it's only a matter of some seconds, i think  i could get used to!

I assume, that the jefa clutch would draw less power than the lewmar one, which takes 1-2Amps!
So maybe i will change the drives immediatly, and put the lewmar for spare !

[SofiaB]

SYJetzt,

When the autopilot is disengaged, 1-2 seconds from pushing the button the wheel will be free.  However, if you attempt to turn the wheel during the 1-2 seconds, it will remain engaged until you release the wheel again.  I press the disengage button, put very light pressure on the wheel and just wait a couple of seconds and every time it disengages.  It's a little freaky though when you disengage, don't wait the 2 seconds, and the wheel is locked and won't unlock in an emergency situation!  This has only happened a couple of times and I now know I must simply wait before attempting to turn.

Stuart
   

[Achilles]

I replaced the Lewmar drive unit (containing both drive and clutch) on my Bavaria 37 Cruiser last year. The clutch had failed. On inspection I found the cabling completely burnt through. The solenoid actuator develops friction so that it draws much higher current in attempting to move it. So it could become a fire hazard.

I ordered the Lewmar replacement from my local Force 4 in Shamrock Quay and they gave me a excellent discount on the list price of £2400. Because Lewmar had no stock I had to wait about 3 months for delivery. Its been working well ever since. Lewmar say the new design is not subject to the problem.

[eriksson.fam@gmail.com]

I Have an original one from 20027 (Bav 42C)
So far no problems, but I wll go on longsailing this autumn.
I didnt know about the problem before. I have changed all controlls to Raymarines new, but kept the Mamba.
Is that a misstake?
//Hakan

[Yngmar]

Hakan, our original one from the year 2000 is totally fine. They were originally designed and made by Whitlock, and at some point Lewmar took over and perhaps did some minor design/manufacturing changes or changed parts suppliers and that must be when the problems started. I've stripped it down before we set off across Biscay and apart from a bit of dust from wear on the clutch plates, it was totally fine and still is a few years and thousands of miles later (almost all of which it was steering the boat).

So your 2002 one is probably old enough to be fine as well, but if you're setting on a big voyage (optimist!), then it's not a bad idea to strip it down, inspect and service it. Or carry a spare, as all things eventually break and the autopilot is quite important when going the distance.

[eriksson.fam@gmail.com]

Thanks for the answer.
I sliped with my fingers.
Modell 2007, so mayby new enough to have the problems. I will take it apart the next week and check.
Håkan