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Checking Voltage Regulator
hulbyw - August 28th, 2014 at 09:31 PM

As my battery has leaked acid out of the breather, a friend has suggested I check the charging voltage. The Bentley manual states that I need to disconnect the cable to terminal B and connect a voltmeter to terminal B then increase the revs to check the charge rate. When I googled it, the instruction was to just put the voltmeter across the battery and increase the revs above idle.
Which method is best? I have bought an Odyssey battery (read lots of $) and need to be sure the regulator is regulating
Cheers.......Wayne


psimitar - August 28th, 2014 at 11:01 PM

B+ disconnected is the no load test of the regulator. To check the charging voltage across the battery is the way.

12.6v is a good charged battery voltage (so ignition and everything off). Then 14.4v is excellent with the engine running above 2000rpm. 13.8v is acceptable but at the lowest end of acceptable.

If on 6v battery then just halve those numbers given :)


hulbyw - August 29th, 2014 at 10:23 AM

Thanks psimitar. I am more concerned that it is overcharging than undercharging. Don't want to cook the Odyssey. It is a 12v
Cheers


Shuffs - August 29th, 2014 at 02:07 PM

Follow psimitar's directions,and you wont go wrong with the checking side of it,but it could just be something as simple as being over full.A little while back,I topped up the cells in my battery with demineralised water,then put it on a battery charger for a while,before reinstalling it,same thing happened,as it became fully charged,it started bubbling out of the breather,did a wonderful job of cleaning the concrete


hulbyw - August 29th, 2014 at 02:30 PM

Thanks guys. New battery installed and I have 14.38 volts when the engine is revved. It is possible the old battery was overfull, but unlikely given that I rarely check it. Maybe it died of old age and neglect
Cheers


Shuffs - August 29th, 2014 at 04:15 PM

Quote:
Originally posted by hulbyw
Thanks guys. New battery installed and I have 14.38 volts when the engine is revved. It is possible the old battery was overfull, but unlikely given that I rarely check it. Maybe it died of old age and neglect
Cheers

Sorry I misunderstood,I thought you were saying your new battery was overflowing,and yep 14.38 volts is good:tu:


psimitar - August 29th, 2014 at 10:12 PM

Quote:
Originally posted by hulbyw
Thanks guys. New battery installed and I have 14.38 volts when the engine is revved. It is possible the old battery was overfull, but unlikely given that I rarely check it. Maybe it died of old age and neglect
Cheers


Oddly enough after topping a discharged 6v battery recently and charging the fluid level rose and spugged out a bit so manybe with the chemistry of the charged fluid it increases in volume.

Of course an overcharged battery basically boils like a kettle and hence why it spugs.