Beta 722 (20 HP) - VOLTAGE REGULATOR ISSUES?

pthorn · Member

Beta 722 (20 HP) - VOLTAGE REGULATOR ISSUES?

Farron · Senior Member

Hello Peter,

The tachometer reads a pulse from the winding of the alternator. If the alternator stops working or a wire connection fails, the tachometer will stop reading.

You state that the alternator has output so I would suggest checking the black/blue wire that runs from the alternator to the back of the tachometer for a loose connection or corrosion. Check both of the 11 pin harness plugs that connect the panel to the engine.

High voltage for this alternator should be about 14.5 volts when a good battery is connected the system. This must be checked with a digital volt meter to verify output voltage. If voltage is high, I would recommend removing the alternator and having it checked at an alternator repair shop. They can easily check output amps and voltage regulation with a spin test of the alternator .

A group 31 battery that requires 1 gallon of water to fill 6 cells has been damaged. It takes quite a bit of charging to dry out a battery like this.

If as you say, the boat sits in the slip 99.9% of the time; I would look beyond the alternator for the problem. Check you shore power charger.

-- Edited by Farron on Monday 21st of October 2013 10:29:47 AM

-- Edited by Farron on Monday 21st of October 2013 10:30:31 AM

Halfmoon · Member

Hi

I would say that you have a VERY bad regulator. Also if you are consistent having to refill the Battery water and the voltage is a 15 dcv you have DANGEROUS situation.

I would not run the engine another minute until you get it sorted out. Have it check NOW...

Tom

pthorn · Member

Hi Farron,

Thank you for your reply. My boat has an older Blue Sea electrical panel with analog meters, so I think verifying alternator output with a digital meter is a great idea. I suspect it's fine as the engine only has about 300 hours on it. I will certainly check that blue-black wire the next time I'm at the boat and thanks again for that clue about the tachometer.

Think I might have two separate problems. Do you think a single stage 5 amp battery charger running continuously through the summer could be enough to boil off an unattended group 31? Does the voltage regulator supplied with the 2006 beta 722 step down the charge output as the battery charges in a similar manner to the way a three stage modern charger works?

Best regards,
PT

Farron · Senior Member

Hello Peter,

Yes, a 5 amp charger can boil off an unattended group 31 battery in that amount of time. The smaller trickle chargers are as low as 1 amp.

All chargers are not equal. It would be wise to invest in a charger that cycles, reads battery condition and adjusts the charge accordingly.

The standard internal regulator used in all alternators will not be a staged charge. You will need an external regulator to get staged charging.

I do not think you are running the engine often enough to damage the battery with over charging from the alternator. I would look to the shore power charging and battery condition.