Front and back doors

When Ada was painted I asked that all the holes for the front and back door catches be filled and painted over. The catches were short cabin hooks. They pushed the doors away from the cabin sides and eventually wore away the paint.
I had some vague idea of using magnetic catches. This proved harder than I expected but today I fixed magnets to all doors and I'm very pleased with the result.

Keeper on front window frame

I eventually found rubber covered round magnets. Rubber covered to prevent damaging the paint where they strike. Off the boat they are very fierce but attached to the doors they apply just the right hold. The steel  back doors strike and hold to the cabin sides. the magnets are pushed out by 4 washers behind them to prevent the doors hitting the back cover fixings. The front doors have a keeper fixed to the wood window frame and the magnets on the doors. the thickes of these is sufficient to prevent the handles hitting the glass of the front windows.

Magnet with spacer washer behind

14 mm gap, just enough
to be clear of the cover
studs

Battery capacity update

Refitting the alternators in the reverse positions went very smoothly. I was concerned that I did not detect any output from the 55 amp alternator before taking it off. However, when refitted it in the primary position it worked perfectly.

The puzzle came as I could not detect any output from the 70 amp alternator in the secondary position. I've used an alternator in this position with the same cabling to charge the bow thruster batteries for 10+ years. After some investigation I found that fitting the warning light resulted in the alternator generating 14+ volts. So how have the bow thruster batteries been charging for the last 10+ years?!

So 3 outstanding tasks:
1. Fit warning light to 70 amp alternator.
2. Connect bow thruster batteries to shore charging cable.
3. Fit advanced alternator regulator to 70 amp alternator.
4. Fit split charge diode.

1. Wire to control panel already in place so need to order lamp holder and fix in place.

2. Currently cable is connected, as per instructions, to domestic batteries and I have no idea how to progress the task.

3. I've order from ebay a replacement regulator with the earth negative field wire already fitted. The wiring loom from my previous failed attempt will need modifying by shortening all the cables but should be a quick job.

4. A future task.

Overall a satisfying days' work.

Battery capacity

In 1997 Ada was fitted with a Lucas A127 55 amp alternator charging the domestic and starter batteries. A couple of years later when fitting the bow thruster I fitted a second alternator, also a Lucas A127 55 amp unit, to charge the bow thruster batteries. About the same time I bought a Sterling advanced alternator regulator but, although I modified the alternator to fit the -ve earth field wire, I did not fit it as there was no problem with the batteries keeping up with our use of 12v power.

With time we added more 12v equipment and began to have power capacity issues. When I got round to fitting the advanced alternator regulator it did not work. I have since realised that marine alternators have isolated returns so following the instructions and connecting the -ve of the advanced regulator to the alternator case does not make a working connection.

About this time we had a problem with the bearings of the domestic/starter alternator so I decided to replace it with a higher capacity alternator. I bought a Lucas A127 70 amp alternator and as the connections were different did some further research about marine alternators. (It was then that I realised my mistake when fitting the advanced regulator.) Fitting the new alternator was straight forward and marginally improved the battery capacity but there were still times when there was not enough battery power.

The original alternator was repaired and carried as a spare. Researching the replacement alternator I learnt that the A127 alternator case has 2 configurations left handed and right handed. As one fited alternator is LH and the other is RH I researched how to change from one to the other.

Latest idea is the realisation that it would be better using the 70 amp alternator to charge only the domestic batteries and to use the 55 amp alternator to charge the bow thruster and starter batteries. This invokes changing the handing of both alternators. Then moving the 55 amp alternator to the position of the original alternator and the 70 amp alternator to the auxcilary position. With the current cabling, the 55 amp alternator is charging domestic and includes a relay. The 70 amp alternator is charging the bow thruster.

All -ve connects are common so no changes to -ve cables. Disconnect the +ve cable from the domestic batteries to the relay. Connect the +ve cable of bow thruster batteries to the relay terminal formally connected to the domestic batteries. A new 10mm cable will be required. Connect the +ve terminal of the 70 amp alternator to the domestic batteries. A new 6mm cable will be required.

Finally, fit the advanced regulator to the 70 amp alternator. For about £10 I can purchase a replacement regulator with a -ve earth field wire already fitted saving modify the existing one.

The alternators are here at home. The major issue is, before taking off the 55 amp alternator I did not detect any output so may not be working. I've changed the handing and it's ready to refit and test. If it's not working I'll bring it home and replace the regulator and rectifier having already watched the online youtube training video! I'll change the handing of the 70 amp alternator when the 55 amp one is proven working as refitting the 70amp alternator to charge the domestic/starter batteries is the fall back position. When both are proven working I'll change the cabling. When that is done I'll change the 70 amp regulator, as this can be done without dismounting the alternator, and fit the advanced regulator.

Then the question will be, how long will it take to recharge the batteries to keep the deep freeze, fridge, satellite TV and inverter working!

Further thoughts now ... I will need to replace the relay with a split charge diode unit. This is to prevent the bow thruster drawing high amps, through 10mm connecting cables and the relay, from the starter battery if the bow thruster batteries are discharged. There is a fuses in the cable that should give protection but it's a bit crude.