Constant Flat batteries on Piper Archer

[mostlytossas]

Anyone have this problem before? I part own with a few others a piper archer II that flattens the battery overnight every 10 flights or so.
The last occurance the aircraft was started to taxi to the fuel bowser ok, restarted and taxied back to the parking bay ok, left for 3 hours then on returning to go flying too flat to crank the engine needing a hand start or jump start. This has been happening for awhile and driving us nuts. The battery is only 3months old and was replaced thinking that was the problem ( it wasn't ). The charging circuit was checked ok. I have numerous times taken a current reading at the battery looking for any discharge and found nothing. My current thinking is maybe the main solenoid is not releasing every now and again and draining the battery though how when everything is turned off I don't know( master switch etc). Has anyone else had this problem in the past and what was the cause?
Hope someone can help with simular experiance.

[stevef]

Is the battery actually flat (check by switching on the landing light, beacon etc) or will it just not start the engine? I remember a long-standing problem like this on a PA28 and it turned out to be a faulty battery lead that wouldn't take the heavy current draw.

[aseanaero]

Could be a bad connection on the solenoid leaving it on even though you have turned the master switch off , check that also.

We had a similar problem with a C402 which was being prepared for a ferry after being unused for 2 years

[NutLoose]

Yes could be wiring, if you have the older Aluminium wiring they used to break up internally and give high resistance, ok, as said have you tried with power on and put everything else on? is there enough juice to power stuff? If it is indeed a sticking solenoid WITH THE POWER OFF AND KEY OUT use the wooden end of a hammer and gently tap the solenoid, do you hear it clunk as it goes over? if so it's sticking.. if it does clunk, shut the cowl and try a start again, had a few where the solenoid intermittantly sticks internally................. A TAP IS NOT BEAT IT TO DEATH ok :)


If the batt power is low, have they put a multi meter onto the main bus bar, ( long copper strip under right footwell on back of C/B.s) one end on the bus and the other on a ground point with the multimeter set to volts DC when running to check the alternator output?

When you do get it running does the ammeter show an abnormally high charge rate?

[mostlytossas]

Thanks all for your input. The battery leads aren't the best though our LAME has said they are good enough,we have decided to change them anyway. The aircraft is wired in Aluminium cables and I have heard this can be a cause for concern so we will look at replacing them at the next 100hrly in April. I will try and get a second opinion first but maybe you could answer me this. If the cables were the cause wouldn't it happen every start? Also how do they "go resistive" if there is no damage to them? ie not squashed or kinked,hit, etc therebye changing their cross sectional area.

[LaceySimon]

Three reasons of battery Flatten.
1- Battery does not get charged properly after use.( terminal cables, charger or charging circuit)
2- Small shortcircuit which is causing battery drainage.
3- Battery is from bad batch. Try more two batteries from different batches.

[stevef]

High resistance in cables can be caused by temperature and moisture as well as corrosion and physical damage (vibration might also intermittently displace groups of broken strands).
I'm more of a spannerman than a sparky but I'd suggest that the only reliable method of testing the LT cables is with a voltmeter under load; a drop of 2 volts will be enough to throw your starting. Arguably, a 'static' ohmmeter test won't help much unless there is a complete break.

I'll be interested to see the outcome.

[mostlytossas]

Just thought I would revisit this old thread and advise all you contributers as to what in fact was the problem. Shortly after all the trouble we were having and following more tests etc which found nothing wrong. I decided to check the battery specs. I found we had a battery that while it was suitable for our aircraft was in the mid to lower amp range than was available. Our LAME just kept replacing it with the same make and size. I also became aware that Gill batteries were having problems with their batteries not lasting for more than a year. We had some that only lasted 9months!
So we decided to try a Concorde R35 AXE the highest rated cranking battery available for our aircraft. We have just now replaced this with another one of the same after 3years and 2 months use. A much better life and trouble free period. Needless to say we won't be fitting Gill batteries to our aircraft again.

[ericferret]

Exactly same issue on our Cessna 150. We fitted a brand new Gill and after a while began to have starting issues. Wife flies it and got seriously pissed off with the lack of reliability. I continued to maintain that the battery was ok. Eventually gave in and changed the battery, all problems gone and have remained so. Dont you just hate it when the pilot is right and double grief if same is also the wife!!!!!!!

We did fit another Gill which leads me to the conclusion that they have quality control issues.

[mostlytossas]

Well Eric I would be swapping over to a Concorde next time especially if you find the Gill dies prematurely. You should get at least 3 years on average from a battery,so long as it is not abused by totally flattening it,overcharging etc. I have since read in some aviation mags about problems with Gill quality control. I believe we have proven it to be true as we went through about 3 Gills before we wised up.

[jxk]

Is the 'make' of battery specified in the TCD or parts catalogue? If so would you technically need a mod to change manufacturer?

[Aviater]

Great to see you got a good result. Simple power problems can be like a thorn in your foot. Painful. Side note. Most battery manufacturers have long lists of aircraft models and corresponding STC's to fit their batteries to your aircraft. Match up your aircraft with the appropriate listed battery model and boom. Job done. Almost. Your actually support to contact the STC holder (in this case, the battery manufacturer) and ask for a copy of the STC and for you serial number to be listed on it. Enter into logbooks. I'll bet 99% of workshops around the world either would t tell aircraft owners this, or wouldn't no the process themselves.

Food for thought.