Friday, April 5, 2013

Low Voltage

It was nearly a 3 year old battery, probably due for replacement. So when I got constant low voltage indications I assumed that was the problem. Wrong.

Changing the battery is easy. Very accessible and the "u" shaped retaining strap is made from light weight flexible aluminum which can be moved out of the way to get the old out and the new in. Unfortunately my flight check did not show any improvement. It wasn't the battery.

Anthony had suggested that it could be the "rectifier". I call it a voltage regulator but he is probably more correct. I called US Sport and spoke with Sam. He said that while it could be a failure, more likely it was corrosion on the multi-connector. Any moisture (coolant) that gets in has no way to escape and corrosion builds up. I took an extended lunch break and went over to check. It is always interesting trying to separate a connector that is designed not to come undone. I worked slowly, deliberately and finally pried the two pieces apart. Green.

Contact cleaner did the trick. I also have a set of micro files (thanks Dad) that allowed me to scrape the internal surfaces. Once convinced I had everything as clean as I could get it I gently put the pieces back together. I turned on the master and instrument switches and everything looked 'normal'. Preflight.
The ground procedures were normal. I did occasionally get a "Low Voltage" warning but the Amps were positive and voltage never got below 11.0.  The wind sock was billowing. It would be a short hop.

We climbed west to 2500' then came back to the southeast and I went through my cruise checks. Everything looked good (and Sally was warnings!) After 30 minutes in bumpy air we came home. I think this one is fixed for now.


  1. Nice job cleaning up the harness. It's always the little things that pop up that drive us crazy.

  2. Glad to hear you were able to resolve this issue.