Battery or Regulator?

[C-NUMB]

Originally Posted by Nos4r2

It won't be your battery in any case. The alternator on that motor is old tech and it doesn't have a massive output. Certainly nowhere near enough to overwhelm a battery the size of the one you have.

Having kind of a similar issue on my Yam 90 AETOL. When battery is fully loaded and the system does not have any power consumtion, voltage goes very high, 15V-15,5 V. But if connecting the running light(40W) or if batter is not fully cherged, figures are normal like 14,3 V.

So this is not then battery related(60AH, slightly less than recomended), would it be a faulty regulator/ recitifier, not an issue to worry about or maybe a faulty/loose isolator swich?

[jyasaki]

Originally Posted by Nos4r2

That'd work, but I wouldn't fancy the consequences if it fell off while trying it out.

If the jumper cable fell off, you'd be running off the battery switch, like you are now.

jky

[doggypaddle]

Originally Posted by jyasaki

But not on the load side. You are, in effect having an intermittent resistor in line with the supply voltage. Any short term spike as the resistance is removed is unlikely to trigger an overvoltage warning on the GPS, as it will be a very short duration event.

jky

really!!
Take it from someone who does Automotive EMC testing that a battery terminal coming loose at high RPM(or dodgy isolator) can cause spikes of well over 120 volts that are sufficient duration ~400mS to shut down ECU's or destroy them. Look up ISO 7637-2 automotive standard Load dump test .

[m chappelow]

Guy in our boat club recently just had to replace the voltage regulator rectifier after it overheated & burned out with using a leisure battery for starting
Lucky another club member is a marine electronics engineer sussed out his problem , told him to change the battery for the recommended one & new rectifier regulator ,,cured it .

[ajstars]

I thought the leisure battery was the type to use? Now I am really confused!!

[Nos4r2]

Originally Posted by ajstars

I thought the leisure battery was the type to use? Now I am really confused!!

There's really no such thing as a 'leisure' battery. Take a read of this:-

Sterling Power Products: What is the best battery to use for an auxiliary charging system?

It should give you a better understanding of what you need.

You certainly won't be causing a problem to your electronics/charging system by using what's laughably called a 'leisure' battery (by clever marketing men) for starting.

You could quite possibly trash a rec/reg unit by trying to charge a battery with an internally shorted cell, but that's not related to the 'type' of battery in anyway shape or form.