Txbyker Posted January 18, 2012 Report Posted January 18, 2012 Over the past few flights my radio has had a lot of static. Today I noticed a high tone in my headset. Then on final from a 2 hour trip I got "HIGH LOW VOLTS" annunciator flashing. I can't seem to find out what that means in the POH but believe it must be the altenator. Could it be that my alternator failed right as I lined up for final? Someone looking over me. Would appreciate any comments about what this could be. Thanks. Quote
jetdriven Posted January 18, 2012 Report Posted January 18, 2012 Find out which it is. We plug a volt meter in the cig lighter when flying. At least on the 77 j the volt regulator has the overvolt protection, anything over about 15v makes it cut the alternator off. Resetting the alt field breaker resets it. Quote
John Pleisse Posted January 18, 2012 Report Posted January 18, 2012 A steady light is "high volts", blinking "low". Was your landing light on or could you rule out your landing light? This is often the single largest draw and most suseptable to buss noise resluting from poor insulation or something shaking loose, etc.. Quote
Txbyker Posted January 18, 2012 Author Report Posted January 18, 2012 Yep the whole HIGH LOW VOLT was blinking slowly. The landing light was on and its a new LED with low draw. I think the light started when I lowered the gear. I will take it to a shop and check it out. I am thinking the altenator was what was making some noise over the headsets for the past few hours and something went all the way out today. Quote
jetdriven Posted January 18, 2012 Report Posted January 18, 2012 Have a look at the alternator there are two wires going to it. Both hav broken on us in the past year. Quote
Dale Posted January 18, 2012 Report Posted January 18, 2012 I had the same problem this past year. I took it into the shop and they found that when they checked some of the wiring that one of the wires had worn through the rubber and had been scraping against the metal causing the High Low Volts Annunciator to come on. It was a pain in the butt finding it, but once they did, it fixed the problem. Quote
laytonl Posted January 18, 2012 Report Posted January 18, 2012 Noise is a good indication of a bad diode in the alternator. Bad diodes will also cause loss of capacity, which would create a low voltage condition under high amp draws. Lee Quote
Txbyker Posted January 18, 2012 Author Report Posted January 18, 2012 Thanks everyone. I went to a shop at my airport and they are going to take a look. The shop believes it is a diode in the altenator too as the symptoms of noisey radios help point it in that direction. Will check the voltage regulator too. If the shop does not get to it by the weekend I will take a look for wiring. Quote
jetdriven Posted January 19, 2012 Report Posted January 19, 2012 If you change alternators the Plane Power is highly recommended. You gain 3 lbs useful load too. Quote
Txbyker Posted January 24, 2012 Author Report Posted January 24, 2012 Any problems in using rebuilt alternators? Quote
KSMooniac Posted January 24, 2012 Report Posted January 24, 2012 You will likely have problems with a Kelly rebuilt alternator. When my Prestolite crapped out about 15 months ago I shopped around and all I could find in a pinch was a Kelly that had been sitting on a shelf for years. Knowing their reputation, I wouldn't touch it even if free, and bought a new Plane Power instead and am very happy. If you know of a good motor/alternator shop and want to rebuild yours, then by all means go for it, but I wouldn't buy a random rebuilt one, especially Kelly. Have I mentioned that I don't trust Kelly? Quote
Txbyker Posted April 10, 2012 Author Report Posted April 10, 2012 Got back from a business trip today and pulled the cowling to get ready for an oil change. Looked at the prop and alternator because something looked strange. The altenator pulley was cocked sideways making the belt angle curve out that caught my eye. After checking the pulley the nut and washer was missing and the pulley had been whipping around on the shaft. If I pulled hard enough I bet I could have slipped the pulley off by hand. I could see a small piece of pulley metal in the altenator. This is a 2 month old altenator. A good shop put it on. I found the nut and washer in the lower cowling where they had fallen. Question - should I ask for a new altenator? Would you feel comfortable if the shaft threads are still good and no metal in the altenator to still use it? I have no idea how a nut and lock washer could come off unless it was not torqued. The shop is good and I do not want to state their name and they are working this dilligently. Just wanted your thoughts on using the same 2 month old altenator. Quote
KSMooniac Posted April 10, 2012 Report Posted April 10, 2012 The alternator should be checked out by a qualified shop for function and especially true-ness of the shaft and pulley. If they are OK, then motor on. I thought that nut was safetied and not a lock nut or washer. It is a HIGH vibration area, so it should have a cotter pin or safety wire. (My manual isn't handy to check) Quote
jetdriven Posted April 10, 2012 Report Posted April 10, 2012 Plane Power and Kelly both were only lockwasher and nut. Should not have come off, though. Quote
Txbyker Posted April 10, 2012 Author Report Posted April 10, 2012 There is just a nut and lockwasher, not cotter or safety wire that I can see. Scott, it is a new rebuilt Kelley. I know, I know. But they shop swore by it and put it on before I could get a Plane Power a couple of months ago. Quote
KSMooniac Posted April 10, 2012 Report Posted April 10, 2012 I could be mis-remembering then... It has been ~ 18 months since I put on my Plane Power. Quote
mulro767 Posted April 10, 2012 Report Posted April 10, 2012 I just went through a similar experience. First, I noticed several weeks ago the scratchy radios when I'd transmit. ATC said I was 5x5 but they were barely readable at times. Climbing out shortly after takeoff this week I got the flashing volts light and reset the cb, no help. One call to Willmar and Brian said "I'm 99.9% sure it's a loose connection on the back of alternator". He was right! There are two wires connected and there should be a tie-wrap holding those wires in place. Mine was detached but the tie-wrap was holding it in place and actually completing the connection. It may have been that way since the scratchy radios began several weeks ago. They are perfect now. But a failing alternator would probably show at lower power settings and higher loads. In which case I'd suspect the brushes or alternator itself. Quote
jetdriven Posted April 11, 2012 Report Posted April 11, 2012 Quote: txbyker There is just a nut and lockwasher, not cotter or safety wire that I can see. Scott, it is a new rebuilt Kelley. I know, I know. But they shop swore by it and put it on before I could get a Plane Power a couple of months ago. Quote
Txbyker Posted April 11, 2012 Author Report Posted April 11, 2012 Byron, I am a 12Volt Lean Machine. I belive that Plane Power is AL12P70. Does that ring a bell? Going with the Plane Power. A&P giving me full credit for Kelly. Update - I found an old post, it is AL12P70. Thanks. Quote
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