Expert: Jeff Grigg - 1/8/2008

Question
First, what a great service you provide with this forum.  Awesome information.  I have a '99 Bass Tracker with a 75 HP Mercury (Force) - my first boat.  I bought the boat used but it seems well-maintained.  Just before my purchase, the previous owner had the voltage regulator and aerator pump replaced.  When I first began using the boat, I noticed the tach did not work at all.  As I accelerated, my fishfinder would freak out.  It worked at very low speeds and with the trolling motor, only.  I replaced a fuse once or twice.  After several outings, I blew the fishfinder.  I noticed other fuses were also blown.  There was one time that I noticed that the fuel gauge was not working.  I could not find any frayed wires.  Neither could local repair shop.  They did replace the inline fuse back by the motor which temporarily resolved the problems.  Tach and aerator worked again.  Within two outings, the aerator began working intermittently.  Then I blew another fishfinder while accelerating!  Any ideas would be a great help.  Thank you.

Answer
Take the boat to another shop that knows what they are doing.
Have them check the rectifier/ voltage regulator. Either it is hooked up wrong, or the rectifier/regulator is bad.
The charging system puts out AC voltage and the rectifier changes it into DC voltage. All of your accessories run off of the battery and DC voltage. If the system was hooked up wrong it will continue to blow fuses and destroy any sensitive electronics from the input of AC voltage into a DC system.
Also check for any frayed, grounded wires.
Jeff