Week of Aug 5, 2013: alternator and battery charger

This past week I worked on a sailboat with a bad alternator and a boat with battery/ charger issues. The sailboat with the bad alternator wasn't putting out any charging voltage. Turns out that the stock hitachi alternator was internally regulated so I had to get a new one no matter if it was the alternator or the regulator that was bad. I learned how to match an alternator to the batteries that it will be charging. A good rule of thumb is get an alternator that is 25% the capacity in amp hours of you batteries. The customer I had had 400 amp hours of capacity so I matched it with a 100 amp alternator. I learned what exactly the Amp hour rating means. For my customers two 8d agm batteries the amp hour capacity was 400 @ 20 hrs. That means these two batteries can handle a 20 amp load every hour for 20 hours. Really cool to find this out. I also diagnosed a bank of two house batteries to be bad and also found that his shore power charger wasn't working which I believe killed his batteries. You can see I pulled the charger apart to find a small piece that was the size of a nickel wrapped in heat shrink with two leads broken off the circuit board. Great week! 

Hours 49

Hours to date  381

Week of July 29, 2013: heat exchangers and windlass's

This past week I have been doing a couple of diagnosing overheats and a couple windlass motor diagnosing. When I have the task of diagnosing a overheat I check the sea strainer, thru hole valve of course, impeller, heat exchanger and  water flow out the exhaust. This boat however had a compromised heat exchanger and was leaking antifreeze out the exhaust so it was necessary to pressure test the heat exchanger. I learned how to test them installed in the boat. I have had a couple windlass motor issues this week too. The first was a slipping motor. The issue was when the customer was pulling up his anchor when he got to the rode the windlass would slip. I determined that the customer was running to small of rode and wore out the two halves of the windlass.

Hours 50

Hours to date 332