Archive For The “Technical” Category

Last summer, our pilot house and master stateroom HVAC units stopped working. Since we’d just got out of the yard in Stornoway Scotland, it was just about 100% certain that the two failures were correlated, and caused by air in the system. We bled the pump and there was air. But when we tested the…

We have a Village Marine STW-600 watermaker that nominally produces 25 gallons per hour. We use it heavily and, over the last 11 years, we have wound up just over 2,000 hours on it. Since the watermaker is such a mission critical component for us, we wanted to have lots of spares on board so…

An engine seldom “just gets better”—close to never—but our generator was leaking vast amounts of oil from the rear main oil seal prior to the cylinder head replacement. If the generator sound attenuation shield front cover was removed during operation, it would spray the engine room floor and the neighboring wing engine, creating a real…

We keep a detailed ship’s log that records where we have been, what we have done, system state, and things we fix. Unlike commercial ship’s logs, that normally are hand-maintained and can’t be modified, ours is a bit primitive in that it’s just a Word document. We focus on it being easy to maintain rather…

This installment of our maintenance series picks up from our previous video, where we replaced the defective cylinder head in our Northern Lights 12kW generator with a brand new one just shipped in from the US. In this video, we complete the job by adjusting the valves, replacing the coolant and bleeding the fuel…

The Stornoway slipway is a big commercial railway that can lift boats up to 50m long and weighing up to 850 tons. The railway cradle uses three pairs of hydraulic support arms to hold boats in place, making for an efficient lift process. Once the vessel is in the correct position, the arms are simply…

This installment of our maintenance series picks up from our previous video, where we removed the defective cylinder head from our Northern Lights 12kW generator and ended with the engine in pieces on the floor. In this third part of the set covering the low power output issue with our generator, we install the…

Batteries are complex electro-chemical devices and sensitive to operator mistakes and charging system configuration errors. Just a couple of deep discharge cycles can lead to early failure. Long periods without fully charging can reduce the capacity of a battery bank. Equalization (extended charge periods at controlled high-voltage charging) can partially reverse some of these effects,…

In the previous installment of our maintenance series, we diagnosed lack of power output on a Northern Lights M843NW3.3 12KW generator with 6,700 hours of use over 10 years. We concluded the #3 cylinder exhaust valve seat had failed. In this second part of the series covering the low power output issue with our…

About four weeks ago, our generator suddenly went from normal output to having far less power. Instead of the 10+ kW it normally produced, it could only generate 7 kW. We worked through the Northern Lights diagnostic procedure and concluded we had a valve or valve seat problem on #3 cylinder exhaust. The steps we…

In this installment of our maintenance series, we diagnose low engine power output on a Northern Lights 12kW generator. This engine is unable to produce more than 7kw of power, but can reliably deliver that, and otherwise is running fairly well. We walk through the diagnostic procedure checking for intake blockage, fuel system problems,…

The overhead space between our generator and the ceiling is rather limited, and the fluorescent light mounted directly above it consumed a large chunk of that. So much so that James recently broke a bulb when jammed over top working to free the exhaust elbow from the exhaust hose. So we decided to remove the…

Our Northern Lights 12kW generator is just a slight bit slower to start. In this video, we check the likely possibilities for slow to start, including air filters, fuel filters, voltage at battery, and voltage at starter during cranking and determine that the starter is at fault. We then show the process of changing…

Our generator showed a light misting of oil around the generator cooling fan a month back. At just under 7,000 hours, it’s a bit early to be leaking, but it’s not a huge issue since rear main oil seals don’t fail catastrophically nor even quickly. It just means that in the next year or so,…

While our cruising lifestyle may be on pause during the Scottish lockdown, our maintenance log isn’t. Several scheduled service items came due in mid-May, including annual testing, lubricating and changing the oil and filter in our gasoline engines, changing the hydraulic zincs, and charging our backup batteries. We also completed some unscheduled maintenance work, such…

One of the challenges with the smaller electrical systems found on most boats is managing the power load. Whenever electrical loads are running on a boat, they are delivered by some power source. It might be the generator, it could be shore power, or it could be the inverter. But, whatever the power source, it…

Saturday morning we lifted the floor covering in the master stateroom head to access stores and found the floor underneath soaked wall-to-wall. We opened up the storage area below and it also had a lot of water in it. The first task was to get everything out of the storage areas and all dried and…

Our Northern Lights 12kW generator ran for years without any hard-to-diagnose problems. It just ran, and that’s the way we like it. For its entire 6,600-hour life, it’s been able to reliably produce 42 amps. It’s nominally a 50-amp generator, but due to highly non-linear load on Dirona, the power factor often is less than…