---------------------------------------------------------- RV6-List Digest Archive --- Total Messages Posted Mon 04/14/14: 2 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 10:55 AM - Marginal Battery Charge when Starting (George Nielsen) 2. 12:52 PM - Re: Marginal Battery Charge when Starting (Charlie England) ________________________________ Message 1 _____________________________________ Time: 10:55:45 AM PST US From: George Nielsen Subject: RV6-List: Marginal Battery Charge when Starting When starting my RV-6 it feels that the charge of my battery is marginal. It does start but the electric motor or battery feel reluctant, as if they will not grant me many attempts and can barely start the engine. I keep the battery charged when my aircraft is parked in the hangar, and the tension in the voltmeter shows around 13V when the engine is not running. Could there be a problem with the battery and is it safe to fly under such circumstances? Thanks. George Nielsen RV-6 PH-XGN The Hague, the Netherlands ________________________________ Message 2 _____________________________________ Time: 12:52:21 PM PST US From: Charlie England Subject: Re: RV6-List: Marginal Battery Charge when Starting On 4/14/2014 12:55 PM, George Nielsen wrote: > > When starting my RV-6 it feels that the charge of my battery is > marginal. It does start but the electric motor or battery feel > reluctant, as if they will not grant me many attempts and can barely > start the engine. I keep the battery charged when my aircraft is > parked in the hangar, and the tension in the voltmeter shows around > 13V when the engine is not running. Could there be a problem with the > battery and is it safe to fly under such circumstances? Thanks. > > George Nielsen > RV-6 PH-XGN > The Hague, the Netherlands Is it a basically 'stock' Lyc with carburetor & magnetos? If so, the only danger to continued flight would be loss of the engine driven fuel pump, in which case you'd need battery or alternator power to run the electric backup fuel pump. Now, how your air traffic control would feel about you losing radio contact might be another issue. :-) Here in the USA, in most parts of the country that wouldn't be a major problem; I live about 15 miles from a Class C airport, and almost never talk to them while flying from my home airport community strip. The easiest 1st test is to get some help to hold your volt meter probes directly on the + & - terminals of the battery (directly on the posts, *not* on the clamps that attach the battery cables to the battery posts). Leave the mags off & fuel to idle cutoff to prevent starting, and crank the engine for a few seconds, observing the voltmeter while cranking. If voltage doesn't drop below around 8-9 volts at at the battery, it's probably good. If the voltage stays up at around 10-12 volts, you probably have a problem (higher than normal resistance) somewhere in the wiring between the battery & starter. It can be anywhere in the path: either battery terminal to clamp, clamp to wire, wire to terminal at master solenoid, etc. Don't forget the return path: starter frame to engine, engine ground terminal to wire, and back to battery negative. You can actually find the problem point with the voltmeter while cranking, but it requires moving the probes to the various points mentioned, while the engine is cranking (not many people are willing to be that close to the prop while the engine is moving, even if only cranking). Here in the USA, almost any automotive parts house that sells batteries will 'load test' the battery using a load that simulates a starter load. That would let you know whether the battery really is dying. If the battery load-tests as good, and starting voltage (on the battery terminals) is dropping below about 8 volts, the starter might be going bad (shorted windings in the starter, or mechanical issues like binding gears or bearings). Hope that helps, Charlie ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message rv6-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/RV6-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/rv6-list Browse Digests http://www.matronics.com/digest/rv6-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.