SO42 DS Bow Thruster Battery

[raybees]

Where is the Bow-thruster battery on a SO 42DS, just in the process of buying and it failed at sea trial. I was not there, does it run on the engine start battery?
Cheers Ray

[fakinx]

Hi Ray and welcome!
Battery for BT is just beside the BT motor in the front section under the bed. I think 70Ah from top of my head. Not engine related at all (except for charging).

[Camira]

Mar 8, 2020 19:51:05 GMT raybees said:

Where is the Bow-thruster battery on a SO 42DS, just in the process of buying and it failed at sea trial. I was not there, does it run on the engine start battery?
Cheers Ray

Hi guys
The bow thruster Battery is an Optima Redtop 50amp.

[ianf]

The battery is under the bed but on mine there is an isolator plunge switch on the vertical face at the head of the bed which keeps getting pushed in (switched off) when guests move around in there. Just make sure, if you have the same arrangement, to make sure the switch is pulled out. 

Also on mine the battery doesn't charge if the switch is off. I thought mine was duff until I discovered this and charged it up.

[raybees]

Thanks for the replies all.
Does any one know what batteries were installed from the factory on this type of yacht in 2010.
Cheers Ray

[Camira]

Optima red top 50amp I believe

[Mistroma]

My 2009 42DS came with an Optima Red Top 50Ah (I think it was the RTS 4.2). It was a factory fitted option (£3,120 + 15% VAT for the bowthruster option). CCA is around 815A, quite high for the size of the battery.

It is in a box on port side at very front of the bows, under the berth. Mine has a large ceramic fuse in the bows and a trip under the berth in the aft cabin.

I had a charging problem with the battery and traced it down to arcing inside the battery connector. The battery post and clamp were dirty inside and poor contact caused arcing. Nothing visible outside, all looked perfect.

I cleaned the post, thoroughly cleaned the clamps (ground away pitting) and assembled with a smear of Contralube 700. I bought a new Optima and switched the original to use as an engine start. It has been fine ever since. In fact the original Optima only died last year and I bought a normal car start battery, so undercharging did not actually kill the Optima.

I obviously caught the fault in time, well worth checking connections and monitoring charge voltage.

[raybees]

Thanks for that, interesting the original lasted so well, surprised you relegated the original to engine start duty, that sounds a brave move!

What about the general start and house batteries can anyone tell me what they were they originally?

[Mistroma]

The original batteries on my 2009 42DS were Tudor 110Ah (110556HD) and they are just lorry start batteries measuring 348(L) x 174(W) x 232(H)mm. I had 4 in total (optional extra on domestic bank, 3 in total).

The domestic Tudor batteries had lost a fair bit of capacity after 3 seasons use and I was planning an extended cruise away from UK. It made sense to buy a new Optima for the bowthruster and relegate the original to start duty. It seemed to have plenty of capacity and a better bet than the original Tudor, even after the previous charging issue.

I replaced the domestic bank with 4 x Trojan T-105s. I re-built the battery box because spec. said T-105s were too big but I seem to remember they were slightly smaller than the size quoted. I might even have managed to squeeze them into the original box. However, not too difficult to adjust the box size. Move one panel every so slightly to port and fit a lower base (plenty of wasted space under the original box). I was able to fit forced ventilation above the T-105s. Jeanneau don't fit any ventilation and the base of the berth was becoming discoloured underneath by the fumes.

[Trevor]

And here's a picture



Regards,

Trevor

[raybees]

Thanks to all for the replies 
I am afraid I have had to put my purchase on hold due to the current Virus situation, so bow-thruster batteries is the least of my concerns at the moment.
Thanks again
I'll be back