Engine,  Sailboat renovation

Alternator charges with too high voltage

April 30, 2019 /

Sunday also meant boat work and it was time to move Anne-Mon from the winter location to our ship. During the summer we will have a spot in a marina further out in the archipelago, but that is pretty far away so it is perfect to have her next to the ship for a while.

Since we have connected the service batteries we also wanted to test the alternator on the engine. We haven’t done this before and during our engine renovation we didn’t do any work with the alternator, we had just hoped that it would work. We magnetized the alternator by applying 12V to the D+ pin with the engine running. That was the easiest way to make the alternator charge as we do not have all the electrical system i place. The alternator started to charge fine but as the battery voltage started to reach 14.6V we decided to stop the engine as it felt like the alternator charging regulator was broken.

We removed the charging regulator to test its function separately. We connected a 10W light bulb between the slip ring brushes (acting as field coil) and applied an adjustable voltage to the D+ pin. For a working charing regulator the light bulb will light up until you increase the voltage above the regulating voltage. For an alternator like this that voltage is approx. 14.4V. Our charging regulator regulated at 14.7V, which explains why it increased to 14.6V during our test run.

We decided that the charging regulator probably is not malfunction but rather set at a pretty high regulating voltage. In our case that might not actually be a problem as we have AGM and SMF batteries which can withstand 15.0V and 14.8V absorption voltage respectively.

We reassembled the alternator and did a new test run and as expected the alternator charged our batteries to 14.7V and then regulated the charging.

Moving the boat from its winter location. Beautiful sunny day, but some really cold winds.

Once we arrived to the ship we started to get rid of all the stuff we have inside the boat. We got a lot of things along with the boat, some useful and some trash. Some of the things are also our tools and equipment we have used while working in the boat. 

The navigation table. This is an old picture but it has looked pretty much the same since then. It’s just the things located here that has changed.
All things removed! The wood on the table is pretty dirty and will need some cleaning later.
The cabin in the stern. One of the beds goes in the same direction as the boat and the other one goes across the boat.  This is also an old picture but it has looked pretty much the same since then. It’s just the things located here that has changed.
Halfway through our cleaning.
Finally we can access this area more easily.
Trying out the bed in the stern. When opening the hatches to the bilge here the whole area gets a very distinct “old boat”-smell.
Definitely needs some cleaning and renovation here as well to make it a cosy area!
Time to sort all of the stuff. We threw away some, but kept a lot 🙂

As we have mentioned earlier we noticed that our batteries was too high, so that the insulation (with aluminum) on the hatch door touches the poles on the batteries. We want to keep as much of the insulation as possible, as the batteries are located next to the engine, so we started trying to removed the aluminum on the hatch door.

Trying to remove the aluminum on the insulation on the hatch door towards the batteries,
Now our batteries are safe 🙂

We have also had some leaking problem with the small porthole from the cockpit to the stern bed (The porthole can be seen on the picture above, when Thomas tried the stern bed). But that was not so surprising that it was leaking, as the old sealing inside was almost gone.

The old gasket inside the porthole.
We cut a new sealing from a rubber sheet we had laying around.

It was really hard to get the new sealing in position, but after some fighting…
…it was in position.
The porthole back in position. Hopefully we won’t have any more leakages here. We still have some leakages in the big “window” in the cockpit. Our future plan is either to remove this window completely or add a proper deck hatch here instead.

We had hoped that the weather would continue being warm and sunny, but the forecast shows around 10 degrees ( 50 Fahrenheit) and some rain for the next 10 days. This means that we won’t be able to continue with the plastic right now, so we will continue with the electrical system, cleaning and other things that come up.

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