[Anonymous]

Anonymous on June 4, 2014 at 4:37 pm #17415

Hi,
I’ve experienced the same thing over the years with my Seneca. Ultimately, I replaced both regulators and both alternators. In your case, since you replaced the alternator five years ago, I would suggest focusing on the regulator. The good news is that they last a very long time and don’t cost much (in airplane dollars). Replacing the regulator will give you piece of mind and get your confidence back in your airplane. Of course, talk to your A&P.

Best,
Scott Sherer
N344TB

[JOEL CADEMARTORI]

JOEL CADEMARTORI on June 1, 2014 at 6:46 pm #17414

The plane starts fine. At rpms below about 1000, the ammeter shows a charge rate proportional to the electrical load. The more devices I turn on the higher the load.
As the engine idles, the charge rate slowly decreases as the battery is recharges after the start up drain.
Everything seems normal until I increase the rpm. At about 1000 rpm the ammeter cuts out i.e. shows zero charge. It stays that way no matter how high the rpms.
However, when I drop the rpms back to about 800 – 900 the ammeter kicks in again after 10 to 30 seconds.
I’ve checked all the breakers and toggled the alternator switch after it kicks out. No help.
The only thing that works is dropping the rpm back to idle.
It is a 1971 140/160 with about 1100 hrs SMOH. The starter and battery are new in January 2014. The battery is fully charged.
I suspect the alternator or voltage regulator. The alternator is about 5 years old. I don’t know the age of the regulator.
Any ideas. Tests that I can try to isolate the problem?
Cheers,
Joel