721lp Posted November 14, 2011 Report Share Posted November 14, 2011 Guys......last night on a night flight the alternator quit charging. Dropped from 14.1 volts to 11.8. I turned off everything I could and only used the landing light for the last few minutes of approach and taxi. Where would a good place be to start looking for the culprit? It's a 1967 C. Quote Link to comment Share on other sites More sharing options...
1964-M20E Posted November 14, 2011 Report Share Posted November 14, 2011 First start with the belt and make sure the alternator is turning. Make sure the belt is tight and there. Second check the main CB from the alternator and make sure it has not tripped. Then check to see if the field is energized. On my plane power there is a separate breaker for the field. If the field is not being energized then it could be a loose connection, bad wire or voltage regulator. If all that checks out then it is quite possible the alternator has given up. If you are handy with a meter and can read the wiring diagrams from the manual all this can be done by you. Then you can go to the mechanic and say change this part. Quote Link to comment Share on other sites More sharing options...
carusoam Posted November 14, 2011 Report Share Posted November 14, 2011 Nice advice 64 E. When self diagnosing, as 64 E has pointed out, I connected long leads (wire) into the cockpit, so I could start the engine and read voltages safely from inside the cockpit. Modern regulators (if you have one) may also have LED troubleshooting indicator lights. You may need someone outside to look while you are operating the engine controls. Best regards, -a- Quote Link to comment Share on other sites More sharing options...
721lp Posted November 14, 2011 Author Report Share Posted November 14, 2011 I will check those things 64 E. I don't think I have a Zeftronics voltage regulator, but it is a solid state one, not the old type. I'll also check the field breaker. You are right, I checked the Alternator breaker on the left side of the panel, but I believe the field breaker is on the right side. P.S. I also ordered this morning a Whelen LED landing light to go get rid of 1 more current sucking device. I already have LED nav lights. Quote Link to comment Share on other sites More sharing options...
DonMuncy Posted November 14, 2011 Report Share Posted November 14, 2011 You might want to go to the Savvy Aviation site and check their past webinar "All About Alternators". Mike Busch does a really good job of explaining in practical terms. Quote Link to comment Share on other sites More sharing options...
jetdriven Posted November 14, 2011 Report Share Posted November 14, 2011 Check the wiring that goes to the field terminal and the output terminal. If the output is loose, it arcs there and displays as an intermittent low voltage, until it melts the output post off. The field terminal wire can break at the crimp terminal or the wiring can break under that shielding. The alternaotor goes offline. Both of these have happened to me, immediately after a superstar mechanic charged me 500$ to install a new Plane Power alternator. Quote Link to comment Share on other sites More sharing options...
1964-M20E Posted November 15, 2011 Report Share Posted November 15, 2011 Good luck finding your problem Any mechanic can make mistakes. My philosophy is that I am my own best mechanic unfortunately the FAA does not see it that way. Like I’ve said before there are some things I would not do even if the FAA said I could but there are a lot of other items that I feel comfortable with but the FAA says I cannot do them without a mechanic sign off. Quote Link to comment Share on other sites More sharing options...
N601RX Posted November 15, 2011 Report Share Posted November 15, 2011 Once you have verfied the alternator is turning and no broken wires, you can determine if it is the alternator or something in the regulator circuit. With the engine running at idle you can momentary connect 12 volts to the field terminal and if the alternator is good it will produce output. If it doesn't then the alternator is bad. If it does, then there is something wrong with the regulator, overvoltage relay, or field circuit breaker. You can connect some long wires for this purpose so you can sit in the plane away from the prop. The regulator circuit can also be checked with the engine off by turning the master on and measuring the voltage at the field terminal of the alternator. It should be around 12 volts. If not start backtracking until you find where you are loosing the 12 volts. Quote Link to comment Share on other sites More sharing options...
721lp Posted November 18, 2011 Author Report Share Posted November 18, 2011 Thanks guys......I will begin t'shooting this afternoon. Will post findings Quote Link to comment Share on other sites More sharing options...
721lp Posted November 18, 2011 Author Report Share Posted November 18, 2011 Good news guys.......the field wire was broken off.....wire stretched too tight and it broke the ring terminal. I extended the wire to take off the stress....works fine noiw. Quote Link to comment Share on other sites More sharing options...
jetdriven Posted November 18, 2011 Report Share Posted November 18, 2011 Ah hah. an 89 cent fix. Those are the best! Quote Link to comment Share on other sites More sharing options...
721lp Posted November 18, 2011 Author Report Share Posted November 18, 2011 Amen, jetdriven. Too bad we don't see many of those. But just hang on, annual is week after next...no squawks to report at this point though. Quote Link to comment Share on other sites More sharing options...
721lp Posted November 23, 2011 Author Report Share Posted November 23, 2011 I just finished installing a Whelen Par 46 landing light. It looks really bright in the daytime, will try it out at night soon and report back. Quote Link to comment Share on other sites More sharing options...
721lp Posted December 4, 2011 Author Report Share Posted December 4, 2011 OK guys.......flew with the Whelen Par46 LED last night. About 1.6. Filed IFR and flew 3 approaches with it. Tower was impressed. Said it was easy to see. Lighting the runway was really good, but not THAT much wider dispersion pattern than a regular bulb, but the COLOR...meaning white....made all the difference. The white runway lines JUMPED out at me. Definitely a plus. Only 1 concern. When I landed and was pushing back into my hanger, I noticed what seemed to be some condensation in the lower right corner of the bulb. It was 39 degrees F last night, don't know if that had anything to do with it or not. I will check today, and if it's still there, I'm calling Whelen. Overall an excellent investment. Almost no current draw, so I left it on all 1.6 that I was up. ,,,,,,,,More to follow Quote Link to comment Share on other sites More sharing options...
rbridges Posted December 4, 2011 Report Share Posted December 4, 2011 Quote: 721lp OK guys.......flew with the Whelen Par46 LED last night. About 1.6. Filed IFR and flew 3 approaches with it. Tower was impressed. Said it was easy to see. Lighting the runway was really good, but not THAT much wider dispersion pattern than a regular bulb, but the COLOR...meaning white....made all the difference. The white runway lines JUMPED out at me. Definitely a plus. Only 1 concern. When I landed and was pushing back into my hanger, I noticed what seemed to be some condensation in the lower right corner of the bulb. It was 39 degrees F last night, don't know if that had anything to do with it or not. I will check today, and if it's still there, I'm calling Whelen. Overall an excellent investment. Almost no current draw, so I left it on all 1.6 that I was up. ,,,,,,,,More to follow Quote Link to comment Share on other sites More sharing options...
721lp Posted December 5, 2011 Author Report Share Posted December 5, 2011 Here's a pix of the finished product......... Quote Link to comment Share on other sites More sharing options...
bnicolette Posted June 9, 2012 Report Share Posted June 9, 2012 Went flying this morning and was heading for a pancake breakfast about 90 miles away. During climb out my JPI started flashing at me with a voltage of 11.6. I looked at the annunciator panel it was flashing low voltage. DAMN I immediately put the gear down as I didn't want to have to pump it down, told approach I needed to go back to the airport for landing. There was no wavering of the voltage other than it decreased a little as I was using battery power only I guess. Back in the hangar I double checked the circuit breakers (Field and Alternator), and they were in. I pulled the cowlings off and checked the wires on the alternator and couldn't find anything obvious and everything appeared to be on tight. I have a Kelly alternator that was installed in 2008 which was an overhauled unit. The regulator was also installed in 2008 and was a new unit. There is only 170 hours since they were installed. I'm curious if this is uncommon to have one of these units fail so soon? (Assuming it is one of these that is causing my issue) Quote Link to comment Share on other sites More sharing options...
jetdriven Posted June 9, 2012 Report Share Posted June 9, 2012 Thats a Kelly for you. Take it to the Auto parts place and tell them its a 1971 Ford F-100 alternator. They can test it. Get a Plane power brand new for 500$, or a Kelly reman for 550$. (I recommend the former) Quote Link to comment Share on other sites More sharing options...
bnicolette Posted June 9, 2012 Report Share Posted June 9, 2012 Is an O/H Hartzell not a good way to go? It seemed like one of the cheaper options? I just had to buy than damn SVS V valve. It's turning into an expensive month. Quote Link to comment Share on other sites More sharing options...
jetdriven Posted June 9, 2012 Report Share Posted June 9, 2012 You think you have an expensive month. I was arguing with my partners about a 1200$ stormscope or a 400$ antenna, now we are staring down the barrel of a 30K overhaul. ! A Beech is looking good right now. That Hartzell ALT-8520 series looks like a Prestolite Ford alternator. 527$ from Spruce. The Plane power AL24-P70 for 500$. One is 1968 Ford. One is Nippondenso, the kind that runs 300K on your Honda. Cheaper. And it nets you 2.6 LB useful load. And, this board is loaded with Prestolite / Kelley / Ford alternaotr failures. Not one Nippondenso, unless you count our 500$ in labor "ripoff shop" who forgot to tighten the output lug which melted our Plane Power and required a 200$ repair. Quote Link to comment Share on other sites More sharing options...
bnicolette Posted June 9, 2012 Report Share Posted June 9, 2012 Quote: jetdriven You think you have an expensive month. I was arguing with my partners about a 1200$ stormscope or a 400$ antenna, now we are staring down the barrel of a 30K overhaul. ! A Beech is looking good right now. Quote Link to comment Share on other sites More sharing options...
jetdriven Posted June 9, 2012 Report Share Posted June 9, 2012 Because the cost to own a Cirrus for a year is the same as your Mooney plus a factory overhaul.....Every year. Quote Link to comment Share on other sites More sharing options...
bnicolette Posted June 10, 2012 Report Share Posted June 10, 2012 The part # on the current alternator is: ALE-8520R I have a 14v system. Spruce is showing the price as $299 which is a factory overhauled unit. Is there a way that I can assure that it will be one of the newer overhauled units from Hartzell? Quote Link to comment Share on other sites More sharing options...
jetdriven Posted June 10, 2012 Report Share Posted June 10, 2012 Sure its not ALY 8520? That's 545$. Check the application guide. One more thing, I forgot. I sold my AL12-P60 Prestolite core to Quality Aircraft Accessories for 60$ and he jumped all over it. He asks "how much do you want?". I think they will give 80$. Oh. I don't know if the problem is the 1968 Ford Prestolite design, or the quality process from Kelly. One owner here had the pulley comeoff after a few hours. Remember the prop has to come off to change the belt. I like the Plane Power better as it gives the full 14.4 V at 800 RPM idle. Perhaps the Prestolite / Hartzell / Kelley will too. HArtzell wasnt making them when ours went West. The Plane Power is new though. You all know how them Nips make their stuff. Bulletproof. Quote Link to comment Share on other sites More sharing options...
bnicolette Posted June 10, 2012 Report Share Posted June 10, 2012 ALY-8420 was removed and the ALE-8520 was installed? I do see the application chart now. (Thank you) Also in the parts catalog it calls for the ALY-8420. Well, so much for that cheaper $300 alternator. Plane Power............Here I come. Quote Link to comment Share on other sites More sharing options...
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