Hello all!
Last year I purchased a Hanse 458. We have the upgraded
Yanmar 80hp (4JH80)
engine with 220hrs.
Recently we had a low voltage
alarm sound on our
engine panel while motoring at approx. 2000rpm. We know now was due to a burnt out
alternator.
The
alternator unit was removed and sent to
Yanmar in Athens for
inspection as part of a warranty claim however Yanmar have concluded that the alternator was not at fault and have stated “automatic
regulator or diode bridge failure”.
They explained that this may be due to to much
current flowing through the diodes (caused by using too many
electrical appliances), reversing the
battery terminals or potentially shutting down the engine
electrical system without shutting down the engine first.
I can say with 100% confidence reasons two and three listed above are not the cause of the alternator failure (because they didn’t happen) and although we do run heaters etc we only do when plugged into
shore power or running the genset.
I have had a second alternator installed and have had a full
electric diagnostic performed by a local electrician here in
Greece to try to diagnose the cause with no luck (he says it’s all reading normal).
This is frustrating because the new alternator is getting very hot and the copper coils appear to be blackening. I am afraid that if I keep using the engine we are going to burn out this second alternator still without having found what the cause of it is. I have only put 1hr on the engine since the new alternator was installed.
I would love some help or
advice on trouble shooting to try an diagnose what might be causing my
boat to be destroying alternators.
Again we have a 80hp Yanmar engine with standard alternator. We have 4 x 160amp
AGM house
batteries with a 90amp engine
battery and a
Victron Battery
Monitor.
Any assistance from those more electrically savvy would be very much appreciated!
Many thanks!
James - sv “INTUITION”
Lefkas Marina, Greece