Long time readers may remember our adventures with our generator shortly after we set out cruising in the fall of 2012. Well, this is a lot worse. Back then I was considering setting the story into epic verse just to keep an overly technical post interesting. I’m thinking maybe this time around I’ll borrow Danielle’s guitar and learn to play a little blues progression and try out a song.
Our last problems involved an irritating oil leak which I am loath to admit that we never actually fixed. We spend an insane amount of money (something like $2,500) and a couple of wasted weeks tied to a dock for the marina to do absolutely nothing beyond identify the problem as a scored crank shaft. Their big idea was to put in a new generator, which had a price tag around $16,000 installed. I suggested an alternative repair which they could not figure out how do so we cut our losses and decided we could live with a bit of a mess and adding a quart of oil halfway between oil changes.
Fast forward to late 2013. For I while I’d noticed that the generator was struggling to reach full power when it was running. Generally it has enough juice to run both air conditioners (not that we run them much), charge all the batteries and still have enough zip to maybe run the microwave or even the water heater if the batteries weren’t drawing too much. As November slipped into December though I started to notice that one of the times we did try to run the A/C it just didn’t work. The engine started laboring and shuddering and the A/C ground to a halt.
At this point the wise idea would be to start sniffing around looking for something afoot. If you are a long-term reader you realize also that the wise choice is rarely the first choice that I opt for. I did some load testing and realized that it really wasn’t putting out much more than three and a half kilowatts (it is rated for six) and any attempt to run loads in excess of that forced the engine to labor, run slow, and drop the voltage below the 240V it was supposed to be making. Not good. But at that time we were getting ready to get to Panama, then go through the canal, then spend time with some friends, then head back to the states for the holidays. The thing was charging the batteries which is 99.8% of what I need it for so just ran it knowing that I couldn’t load it up too much.
When we returned from the states we got back to the boat, aired it out and started slowing unpacking and reorganizing. We’d been parked at the Balboa Yacht club since we cleared the Panama Canal in December and it was more expensive than we liked to stay there (meaning it is not free). So our short-term goal was to restock the boat with some perishables and frozen foods them move to the nearby Las Brisas anchorage where we could reorganized then head out so someplace nicer. Well, on our second day in Las Brisas suddenly the generator just stopped making any AC power altogether. Not an Amp of 240V power was forthcoming, though the power meter did register 8V of power instead of 240V for some reason.
This was not good, though not fatal, as the generator still makes power to charge the 12V and 24V batteries even if the “Generator” part (which makes the AC power that drives the big, serious battery chargers) wasn’t switched on. So we could charge while I searched for a solution to the problem even though it took a LOT longer.
Then things got even more interesting when the generator just up and stalled. It would run for a while…then stall. Usually that is a fuel issue, but a quick change of the primary fuel filter didn’t fix it. So at this point we basically have no generator at all which is a big problem since our solar panels and wind generator on a sunny, windy day at best are supplemental charging. We started shutting things like the freezer off to cut power consumption and extend our need to recharge. This was an interesting experiment because we found that by avoiding electrical consumption diligently we could extend the battery charge out several days. Of course we couldn’t make water, run the freezer, use the microwave, etc. etc. so life was getting primitive in a hurry. We had to fix this, or find SOME way other than pulling the anchor and driving the boat in circles to get charged up.
Warning! Technical Interlude
Your typical boat “Generator” consists of two basic parts. One is a diesel engine, like any other engine. It’s job, like any engine, is to run which makes the crankshaft rotate. The general principles of engine power is that the spinning crankshaft is attached to other things like transmissions (to provide driving power to wheels in a car or a propeller), belt and pulley systems (like those that drive the alternators in a car) and so on. With a boat generator the crankshaft is basically used to spin a magnet inside a big coil of wire.
AC Power is generally made my spinning a magnet inside a large coil of wire.
A bridge rectifier. About $5.00 if you pick it up at an electronic shop, or $35.00 if you buy it from Westerbeke
The motion of the magnet induces electrical flow inside the coil of wire. Because of the di-pole nature of magnets (with a North and South pole on them) as it spins the current reverses direction with each pole. Hence the term ‘Alternating Current’ as the current flow goes back and forth like a tide 50 or 60 times per second. To made DC or Direct Current you need to “rectify” the AC current with something called a “Bridge Rectifier” which takes AC in and puts out a slightly lower voltage of DC out. A Rectifier is basically a bunch of diodes (one way electrical gates) that are wired in such a way that the back and forth flow is converted to a single direction.
If that wasn’t dull enough here is a diagram of a bridge rectifier.
The reason this is important is that there are many places this can break down. Newer generators do not use things like brushes, and the magnets are not fixed magnets either. Rather the magnets are electrically magnetized, and the generator users some of its own AC power rectified to DC to magnetize things more and make more power in a loop. These coils (or windings) are “stators” and include coils of wire and diodes for various purposes.
End of the Techno-babble (for the most part)
The question which I am sure is burning in your mind is “So what could possibly be wrong with Evenstar’s generator? And why did he make me read all that incomprehensible stuff?”
Well, I started testing on my own and ruled out the boat wiring (since the AC was dead right on the generator) and started looking into some other tests. I called in some local cruisers that are in the repair business. They poked and prodded and determined they thought it was the Bridge Rectifier. I was dubious since I’d seen behavior before it failed that the Westerbeke troubleshooting guide suggested was the Main Stator. We went to an electronics shop and got some new rectifiers…no dice. Next I spent a day poring over the shop manual trying to match the wiring diagram colors and pictures to the practical reality of what was on the engine. By the end of they day I was pounding my head because most of the tests used to verify parts of the stators and windings as good involved placing test leads on wires or parts that did not exist or that we could not find. The work space is tight in there and it is hard to see, but there were clearly differences between the Fine Manual and what is installed in my engine room.
Eventually we all despaired of using the shop manual to solve this, and I called the local Westerbeke distributor and he sent some fellows out that didn’t speak a word of English to take a look. Eventually we conveyed the nature of the problem to them and they did some tests and came up with the Main Stator winding as the problem. They came back the next day and took it off – this involved completely disconnecting the generator, pulling it off its mounts, rotating the 450 pound engine in place so they could get to it to take it apart, and pulling about 1/3 of it off to bring in.
So now we wait for a week while the Main Stator is rebuilt in Panama City.
I become “THAT GUY” in the anchorage
I’ve always hated little gas powered generators. They are noisy and they must be run outside so they get put up on decks or on sterns to rattle away. It seems that in some locations there was always “That Guy” upwind of you that ran his stupid little generator all evening. Perhaps there was a bit of snobbery there, as our generator was large, sound proofed, and you couldn’t hear it sitting in the cockpit, never mind 100′ away from us. 
Well, I have met the enemy and he is us. To meet our charging needs in this (and any future) generator crises we had to do something so we picked up a Honda 2000i generator. It’s not actually the worst thing ever. It weighs about 47 pounds and is about the size of a fat sewing machine case. The 2000 is it’s maximum rating, the 1,600 watt working limit is enough to get an adequate amount of charging in the four hours it runs on a gallon of gas. It needs to run a few hours more than that to get a full charge on the house bank though.
Is it quiet? Ostensibly it is – the literature says “as quiet as a conversation.” Well I suppose it is, when it is idling and under no load. If you load it up with a boat that will take every Watt it is making …you can hear it. Fortunately we are in a big anchorage with enough wind and space between boats that nobody can really hear my shame.
