This is why external voltage regulators are preferred.
Hi,
I'm stuck in the middle of no where with an alternator that's putting out 16+ volts. What should I do?
1 leave the plane and make my way to a town
2 fly with the over voltage. Nearest airport with service is 45 minutes away.
3 fly on battery only. Not my first choice with dual electronic ignition.
Need some constructive advise.
Thanks
You do not mention if you have an internal or external voltage regulator. If you have an external regulator you can go to town and replace the voltage regulator. A second option would be to run with battery only till the battery voltage drops down to about 10.5 volts. At that point, turn the alternator back on and let the alternator charge it, until the voltage starts to exceed 15.0 volts. At that point, turn the alternator back off. Repeat as needed to get to that airport with service. The low battery will act as a temporary voltage control, as it will act as a heavy load on the alternator, till it approaches a full charge.
With an internal voltage regulator, your options are limited to going to town to either buy a voltage regulator and installing it yourself, or taking the entire alternator into town to have someone do that for you. FYI, if you have a Nippon Denso alternator, the voltage regulator can easily be changed in about 15 minutes, without splitting the case halves of the alternator.
I have some photos which show how this can be done, if you need them.
Gil's advice about checking for a bad wire connection won't help, unless you have a mechanical, external regulator. A poor connection to the field wires would cause an under-charge condition, not an over-charge. Your problem is caused by the voltage regulator shorting out [solid state model] or sticking [old school mechanical regulator]
The old mechanical units can sometimes be temporarily unstuck, by rapping on the cover. This would be a temporary solution, at best.
Flying without doing anything risks destroying your battery, radios and avionics.
Charlie
PS If you need the "how to" photos, contact me off list, via either email or Private Message. You can email me by clicking on my user name, then choosing the SEND EMAIL TO link. There is also a slight possibility [certain V/R designs] that the wire to one of the brushes has broken and has contacted the case of the alternator.