This morning I was very pleased with myself because the generator started all by itself.  Last night I installed a little gadget for that purpose and it worked beautifully.

Starting the generator automatically has always been on the project list, but seemed like a solution looking for a problem, so it never made it near the top.  It wasn’t until we moved aboard and spent some time away from the dock and shore power that we realized that running the generator was an essential part of our power diet.  If nobody were here to start the thing, our batteries would die and the refrigeration would shut down.  It meant we couldn’t leave, and suddenly an automatic generator start became more important.

Yes, we have a large solar array, no, it isn’t enough, and yes, our refrigeration is grossly inefficient.  If we were going to be gone for a long period, we would probably throw away all the food and turn the refrigerators off.  But if we only want to be gone for a few days, it’s better to keep everything running while we’re gone.

Another part of the problem was finding the right unit.  It is most common to find the generator start capability as an optional add-on to higher-end inverters.  Our inverters have the capability, but not the option, and they’re too old to find the necessary module.  Plus, different generators have different starting requirements, and we needed a unit that had the flexibility to start our Northern Lights.

It wasn’t until the project received priority that a search in earnest began.  It yielded a few hits, but none as clearly perfect as the GSCM from Atkinson Electronics.  A call to the company had one on the way $249 later.  Installing it was really no more difficult than looking at the back of the Northern Lights’ control panel and wiring the GSCM to the appropriate switch contacts.

Most of these units are designed to work off battery voltage to determine when the generator is needed for charging.  I could do better since I have a Victron BMV-600 battery monitor that watches the Amps flowing in and out and calculates a precise depth of discharge.  The battery monitor allows me to set thresholds at which it will energize a relay, perfect for signaling an automatic generator start if the unit supports it, which the GSCM does.  I will add a Flexcharge programmable timer to institute quiet times when the generator can’t run.  Typically I only want it to run between 9 and 11am, and when the battery is below 85%.

If air-conditioning were important, I could also use the timer to make the generator start on an interval, or use a demand device like a thermostat to start it.  But that gets back into solving a problem that I don’t really have.

I finally got a mechanic down to the boat last week.  I’ve been meaning to do this since before I bought the boat, but never got around to it.  I knew the news would be bad.  Do they ever give good news?

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As previously mentioned, we lost the port prop shaft during the delivery trip.  This occurred when we reversed the propeller to spin off some sea grass that had accumulated and was slowing us down.  Fortunately, the zinc nut on the shaft could not pass through the strut and the shaft stayed under the boat, but the end of it was inside the stern tube and could not be accessed from inside the boat.  This morning I had a diver down to the boat and he pushed the shaft back in for me.

One of the mysteries about the shaft problem was where the shaft key went.  This is a piece of 5/16" square rod that fits into grooves cut into the shaft and the coupling to keep the former from turning inside the latter.  The key should have been somewhere in the bilge, but it wasn't.  Improbably, it emerged from the shaft seal along with the shaft.  I had assumed that the last mechanic to pull the shaft put it back without the key.  I had gone through the trouble to take the starboard shaft out of its coupling and have that key duplicated.  Oh well, now I have a spare and the starboard side got new bolts and set screws in the bargain.

Getting these couplings apart was a bit of an adventure.  Being of light displacement, our boat's bilge is much shallower than that of a typical sailboat, but it has all the same stuff crammed into it.  Combining the tight quarters with some very stubborn bolts, the job looked impossible for many hours.  When confronted with this type of problem I usually end up at Home Depot staring at the tools I don't have and imagining how they could be employed.  In this case I bought about $150 worth (no such thing as too many tools!), but the answer lay in the $12 pipe wrench.  The first attempt with the pipe wrench failed for my lack of understanding how it works (well, have you ever used one?).  I think I would have nailed it on the first try with a chain wrench, but HD doesn't sell those.  Success came when I discovered that the pipe wrench's teeth are angled so that it only works in one direction.  You learn something every day.

Once I had it apart, I took it all over to General Propeller and they supplied me with a new shaft key and new set screws.  These set screws were drilled, so they can be wired and hopefully we can avoid this little exercise in the future.  One oddity was that all the set screws (two on each coupling) were 10mm, but one of the screws on the port coupling was 1/2.  Looks like maybe somebody couldn't get the screw out and ended up retapping it.  But the dimple on the shaft that the screw fits into wasn't any bigger.  I wonder if this could have contributed to the shaft slipping out.

The shaft seal itself was in bad shape and leaked heavily after the shaft was back in.  Fortunately, I had proactively purchased a spare on eBay and could replace it.  It had probably worn out and begun leaking during the delivery but wasn't noticed.  Turns out these seals are water lubricated and are supposed to be "burped" when the boat is put back in the water to avoid an airlock in the seal.  Even though it has a Volvo Penta part number (828416) stamped right on it, Volvo doesn't have any record of the part.  I've read elsewhere that this was equivalent to #828422, but this is for a 30mm shaft and mine is 32mm.  I'll keep an eye out for the 416's and buy any I find, but I should probably get a 422 just in case.

The port shaft seal is additionally challenged since it has to make up for an alignment issue on that side.  The way it has been explained to me, the stern tube and the strut are not aligned with each other, making it impossible to align the engine with both.  The correct solution is to rebore the stern tube, but that sounds like as much fun as getting a tooth pulled.  The more expedient remedy is to align the engine to limit the wear on the cutless bearings and accept the fact that they'll wear faster than usual.  With the misalignment the tolerances are so tight that the normal vibration of the engine transmitted to the shaft causes it to knock against the stern tube at some speeds which is not a pleasant sound.  Pretty much sounds like a hammer banging on the bottom of the boat.

Once everything was back together, I ran the engine at the dock for awhile, revving it up in forward and reverse.  Everything stayed together, but I didn't have the nerve to stress it in hard reverse.

The diver told me that I had barnacles growing on my propellers.  This was a surprise since I'd just had them treated with Propspeed.  I knew Propspeed wasn't an antifoulant, but didn't know that the barnacles could still adhere.  He said that if I ran my propellers periodically they would come off pretty easily in the wash.

We had a small electrical problem a couple weeks ago.  While making breakfast and running the air conditioner one morning, we got one of the conductors in or 220V wiring hot enough to melt through the insulation and short against the other conductor.  This caused our 50A shore power breaker to trip.  That put an abrupt end to the air conditioning, battery charging, and pancakes.

The wires in question are 8 AWG and more than adequate for carrying 50A at 110V.  I’ve seen the stove pull an impressive amount of power, but the breaker should have tripped long before any wiring was damaged.  If our breaker failed to trip for some reason, there is another 50A breaker on the dock that would have.

Where the short occurred was immediately after the transfer switch that selects between shore power and generator, and I later discovered that the switch itself would no longer turn.  Did the switch fail internally and cause the problem, or did a bad wiring connection cause the heat buildup and melt something inside the switch?  I’m betting on the latter, since I discovered some corrosion in the connection.

The switch itself is a Kraus & Naimer C42 A212 and not the kind of thing you can walk into a local store and pick up.  But I felt fortunate that the first call I made to a marine electronics shop yielded the part in inventory.  It was in my hand two days and $275 later.

Replacing the switch and burned wire was unremarkable except for the mechanical challenges of crimping 8 AWG.  Most crimpers only go down to 10 AWG.  I bought an uninsulated barrel and a crimper that could handle 8, 6, 4, and 2 AWG.  After crimping, I covered the splice with heat shrink tubing.   I did not put any type of dielectric grease on the connection,  but I’m wondering if I should have given the corrosion.

In the current setup, the boat’s 220V ammeter only measures the black conductor the circuit.  I wonder if it would be advantageous to install a second ammeter for the red conductor.