Debugging alternator issues
Debugging alternator issues
Picture of Arnd

Arnd

2024-05-27 Unwelcome surprise aboard Zanshin

Early in the day

I wanted to sort out some items at work and fired up my AC systems. The water kettle consumes 2000W, so I like to run the engine while doing that. The alternator will charge at about 90A (at 24VDC) and when the kettle is running the net charge isn’t negative. I then let the engine put in power for 10-15 minutes until the charge runs down to 50A. Then the solar panels will usually fill up the bank during the course of the day.

While drinking my coffee I saw that my bank was only charging at around 10A. I checked all the electrical devices and didn’t find the source of the heavy drain. Then it dawned on me that the alternator wasn’t working correctly. I checked the engine compartment and saw nothing bad but turned off the engine anyway.

Morning
The bottom one is broken
Of course, the bottom one is broken

I had some meetings online, but my mind was on my alternator problem. I had opened all the engine compartment hatches to let the system cool down enough that I could work on it comfortably.

I had to disassemble much of the galley storage to access the back of the alternator. It took a long time isolate and remove the cables; then the small Phillips head screw holding on the regulator on the back section of the alternator didn’t open and I managed to partially strip it.

Tools laid out for the alternator
Tools laid out

By this time, it was after 5PM and I chose to distance myself from the problem and shower before going ashore. Needless to say, I wasn’t going anywhere on Zanshin before I had a plan, and I was in a less than stellar mood because all of my plans had to be changed.