New owner - B39 - many questions!!

[Captain Golla]

Hi everyone
I am in the process of buying a 2005 Bavaria 39 in Thailand. Have completed the survey, sea trial and haul out, and I am going ahead with the purchase. I have owned other boats before so I am quite handy, but I am a complete newby w.r.t. this one. I will be doing lots of remote coastal cruising in SE Asian and mostly Indonesian waters.
My first question regarding the ST4000 autopilot which is fitted to the wheel. During seatrial it could not keep the boat on course (under sail). Its a condition of sale that this be repaired/serviced. Thus my question: is this a reliable autopilot? Its been on the boat since 2005 so I assume it must have worked well previously? I am not planning on doing long passages, but definitely will be using the autopilot a lot, lots of 1-3 day sails ahead shorthanded. I am very keen to hear from owners who have this autopilot as I assume it must have come as a standard (or bottom of the range) equipment on many of the B39's?
Thanks a lot
Golla

[JEN-et-ROSS]

My brother has a Gibsea 372 with an ST4000 on the wheel. It gave good service until on day he was sailing under 'Genny' alone. Not realising that the unbalanced sail plan on a broadreach was putting such a load on the rudder he was taken by surprise when the Wheelpilot 'exploded/disintegrated' sending a shower of little wheels and plastic bits over the cockpit, never to work again.
It's since been replaced with another ST4000 and is again giving good service.
I guess the secret is not to overload it and it will be fine.
As for not giving an accurate coarse, it probably just requires it's 'settings' altered. Our own Raymarine autopilot has a 'power saving' mode that only makes infrequent course changes to reduce the battery drain.

Incidentally our B38 has a 'Type 1' Raymarine actuator arm fitted to a quadrant on the rudder stock, this does look like a better arrangement..............Bill

[Ziffius]

The reason it has a wheel pilot may be due to the steering arrangement on your model - see the link to the problems when I bought my Bav 39 (2005/6 vintage) and tried to fit an AP

http://www.bavariayacht.info/forum/index.php/topic,323.msg1676.html#msg1676

Hope your AP is fixable.

[Symphony]

The 4000 is not the best autopilot and is over the limit of its capacity for your boat. However it is often fitted because of the difficulty of fitting a below decks pilot. it should be fine under motor and suggest you recalibrate it following the instructions in the operators manual. If you don't have this you can download it from the Raymarine website. If it then performs under motor you will know that the control unit is working. Double check that there is not anything metal close to the fluxgate compass which will probably be in a locker in the aft cabin, or in the lazarette as this will upset the control unit.

When you use it under sail you need to trim the sails so that the boat more or less sails itself with little weather helm before engaging the pilot as the motor is not powerful enough to deal with high loads on the helm, and as noted above, it can result in failure of the gears.

Provided you don't use it in heavy weather it should be adequate and useful for steering under motor.

[Captain Golla]

Thanks everyone. I downloaded the st4000 manual and read that the st4000 is too 'lightweight' for the B39 which displaces around 8500kg's.
According to the manual:
Tiller Drive Actuator GP conversion kit (W003)
This GP conversion kit (W003) gives the option of converting the ST4000+
which has the power to helm boats of up to 6,500 kg (14,300 lbs)
displacement, to the ST4000+ GP which would push the limit up to 9,000 kg
(20,000 lbs) displacement.

Has anyone done this conversion??
shotto

[jezzb]

I had the St4000+ on my Bavaria 30 and had to change the gearbox twice in 9 years. It does not sound much maybe, but I hardly use the autopilot. The small gears inside the gearbox are made of nylon and they are not that strong.

I did not do the conversion you mentioned but if it was me, I would go for a more robust model.

Good luck

Jezz

[Spirit of Mary]

I use the ST4000+ on my BAV 38. As you allready found out it is undersized for my boat. For a BAV 39 it is way undersized. Up to wind force 4 it does the job, but beyond that you have to take over by hand. I could get it working only after I installed a rudder position sensor and after I used a calibration not from the manual but which I got from a member of the Dutch Bavaria sailing club. Before that it was not keeping a straight course but just swinging till "off course" under sail and even when motoring.
In the setting you have to set it f.e. as a ST5000.
The most safe way is to buy a below deck linear 1 drive. I hear only positive things about this drive.  Of course you have to buy also the new controls for it (quite an investment).
Ger

[Symphony]

Thanks everyone. I downloaded the st4000 manual and read that the st4000 is too 'lightweight' for the B39 which displaces around 8500kg's.
According to the manual:
Tiller Drive Actuator GP conversion kit (W003)
This GP conversion kit (W003) gives the option of converting the ST4000+
which has the power to helm boats of up to 6,500 kg (14,300 lbs)
displacement, to the ST4000+ GP which would push the limit up to 9,000 kg
(20,000 lbs) displacement.

Has anyone done this conversion??
shotto

Never come across this, but by the description think it must be related to the tiller version of the 4000 rather than the wheel pilot. anyway the ST 4000 is now obsolete and replaced by the SPX5 which uses the same drive unit but a more sophisticated control unit. The size limitations are the same though.

[Captain Golla]

Thanks everyone. I am also seeing on other forums that its not uncommon to install a 'too small for the boat' wheel drive autopilot... Its whats on the boat so I am going to have to make do. Its mostly for motoring so hopefully it will do the job for that. When I am under sail I will be keeping a close eye anyway... at least now I know what to expect.