lukejb Posted December 28, 2014 Report Posted December 28, 2014 Flew a 400 mile Xcountry out to NM yesterday and just after leveling off after departure the volts light flashed for about 10 seconds then quit for about 30 seconds then started flashing again for another 10 seconds then quit and the rest of the trip (almost 2 hours) it was fine and not flashing. Both times when it started flashing I checked the voltmeter and it was at 12 volts so I guess it was not charging. It is normally at 13.6 or 13.7 volts and was at this for remainder of flight after the brief flashings. Planning on having it checked out after we get back home. Any ideas on what might be going on? Is this an indicator the alternator is about to fail? Any reasons I would need to get this looked at before our flight back? We will be flying back VFR but still would not like to have an loss of my electrical system on flight back.... Quote
BigTex Posted December 28, 2014 Report Posted December 28, 2014 Luke, It sounds like the same issue that was discussed a few time in the last couple of months... Here's the latest thread. http://mooneyspace.com/topic/13946-trouble-shooting-a-low-voltage/?hl=voltage 1 Quote
carusoam Posted December 28, 2014 Report Posted December 28, 2014 did you mention what you have for voltage regulator or alternator or belt? then there is the wiring to the alternator that is worth a good tug. if you don't see the higher voltage, then it is not charging. flying without batteries is possible,but you need mode C for most places around me... is your GPS battery powered? i have not flown far without an electic system... best regards, -a- 1 Quote
DonMuncy Posted December 28, 2014 Report Posted December 28, 2014 If I was doing it, I would fly it home and have my regular guy check it out rather than "pot luck" with whoever you find there to look at it. But I would not do that if it was IMC, and I would watch the voltage like a hawk all the way home. If your voltage was 13.6 for a half hour, your battery is most likely well charged. If the light starts blinking or the voltage drops down near 12v, I would find the largest airport (where you have the best odds of finding a decent technician) within 10 or 15 minutes and land. 2 Quote
lukejb Posted December 28, 2014 Author Report Posted December 28, 2014 BigTex thanks for link to the thread. I read through it. Carusoam I am not sure what I have for voltage regulator it is a 77J. I have a panel mounted GPS but fly the iPad and always have a fully charged backup iPad as well.... Don I like your advice and I think that is what I will do. Since it was fine for the last 2 hours of the flight I feel ok about it but will watch it very closely and land if I have an issue that does not clear up on its own. Quote
carusoam Posted December 28, 2014 Report Posted December 28, 2014 with time... start researching the plane power and zeftronics sites... best regards, -a- 1 Quote
mooney2201 Posted December 28, 2014 Report Posted December 28, 2014 had the same problem with my mooney...voltage regulator,had to open it up.mylar insulator fell apart on main regulator.and was shorting to the case...if its the origional regulator,this could be the problem.alot of vibration under the panel on the right side...they are cheap around 200 dollars.easy fix if you know anything about electronics...zeftronics will have the part Quote
tony Posted December 28, 2014 Report Posted December 28, 2014 make sure the iPad is charged up, get a fresh set of batteries for the walkie talkie, turn off all unnecessary gadgets, and press on........ Quote
Danb Posted December 28, 2014 Report Posted December 28, 2014 Also don't discount the annunciatior panel may be problematic, I have a low volt light flashing issue for the last annual and the MSC could not fix it without returning it to the factory for over 1 amu...if I push on the panel it stops ...I have backup in my 1000 so I know the system is working..frustrating Quote
ArtVandelay Posted December 28, 2014 Report Posted December 28, 2014 I had this problem too, shortly afterwards my battery died, so far with new battery it hasn't reoccurred Quote
TTaylor Posted December 28, 2014 Report Posted December 28, 2014 I had a similar problem about two years ago. Finally found a loose connection on the regulator wiring. As always start with the alternator belt, alternator mount, alternator, and regulator. Intermittent fluctuations can be the hardest to find. Quote
Tommy Posted December 30, 2014 Report Posted December 30, 2014 I had a similar problem too! It's probably not the problem with announciator panel as your EDM showed 12v bus voltage which is the battery voltage and your amp metre is showing discharge. So it is very likely you have a faulty charging system. Mike Busch from EAA has a very short but nevertheless fantastic webinar video showing you how to trouble shoot this problem in a methodical way. Whilst I vehemently discourage anyone to fly without an airworthy charging system, on my J (again, DISCLAIMER: your J is not necessary the same as my J) it is possible to fly couple of hours with a fully charged battery and had all the necessary avionics turned on. I did it thru my own ignorance and luckily got away with it. BUT the biggest risk you are actually running is that you might not be able to get the gear down or operate the electrical trim. So if you really want to fly it back to your own mechanics, do this (again, highly discourage you to do so especially if it's a long x-country flight) 1) trickle charge your battery (determine the voltage, and never charge with anything more than 10amp, 4 amp is ideal). This may take 12 to 24 hours depending on the health of your battery and temperature. 2) minimise the use of any unnecessary avionics. 3) carry a handheld radio. 4) watch battery voltage on your EDM anything less than 11.6v means your battery is at least more than half drained. Drop your gear and fly like that all the way to the nearest airfield. 5) learn on how to manually deploy gear and trim and flapless approach. I know I am going to cop it left right and center for this but what can you do if you are stuck at a field without a A&P? 1 Quote
lukejb Posted January 4, 2015 Author Report Posted January 4, 2015 Tommy, No unfortunatley not yet. We had originally planned to fly out on Friday but weather did not cooperate. We did have a nice day earlier this week so i took it up just to see if the volts light would flash again but it did not and the voltage was at around 13.7 on the meter the whole flight so hoping everything is good for our flight home and i will get it checked out next week..... I have battery on a trickle charger and will be watching annunciator and voltage closley on the flight home.... I wil update after i get my mechanic to look at it. I was talking to another mechanic about it and he was saying it can be very hard to troubleshoot electrical stuff like that. I am going to try to watch the Mike Busch webinar as well if I can find it... Quote
DonMuncy Posted January 4, 2015 Report Posted January 4, 2015 It is surprising how simple it is to troubleshoot a charging problem, if it is not charging at all, and how difficult it is to troubleshoot one that is intermittent. Quote
lukejb Posted January 4, 2015 Author Report Posted January 4, 2015 Flew home today. Two hour flight and no issues or flashing of the volts light..... The voltage meter stayed right at arounf 13.7 volts for the entire flight..... Took off with about 3 inches of snow on the runway, that was a first for me. Not sure what proper procedure is for it but i treated it like a soft field take off and it seemed to handle it just fine. Quote
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