rbuck Posted January 23, 2015 Report Posted January 23, 2015 So, I got in my plane today, with a friend of mine, ready to head to Columbus, GA to see my brother graduate from Ranger School. Got all fueled, pre-flighted...and the plane wouldn't start. I did my normal startup procedure, propeller kept turning over, but the engine just didn't catch. Someone at the airport mentioned that it might be a shower of sparks not sparking the initial ignition. Does that sound like a feasible problem, or could it be something else? Does anyone have any experience with this? Quote
N601RX Posted January 23, 2015 Report Posted January 23, 2015 If you are noticing kickback as you release the key from the start position then it is something with the shower of sparks or the left mag. Are you hearing the normal buzzing sound from the shower of sparks? Quote
ryoder Posted January 23, 2015 Report Posted January 23, 2015 My ignition switch died recently. Expensive part. When you push in the starter vibrator should energize. If it doesnt it might be the switch. You could probe the switch but I left that to my A&P. Switch was like 350 bucks. Quote
jamesm Posted January 23, 2015 Report Posted January 23, 2015 If you heard buzzing from Shower of Sparks (aka starter vibrator) while statrting I would suspect the retard points in the left magneto. If you did not hear the the buzzing you could take retard lead from the left magneto to see if you have conitnuity while push to start on the ingintion switch (I would disconnect the starter first and for safety reason). If you do have conyiunity it is posible the ingition / cigar lighter ciricut breaker (Ithink it is 10Amp) has failed or gone intermittant. It also possible if you have original wiring in the airpane that one of the connection on one terminal has gone bad. JamesM. '67C Quote
Hector Posted January 23, 2015 Report Posted January 23, 2015 If you have Bendix magnetos I would check the P-leads. This has happened to me before exactly as you described. The P-lead will have either a hex nut or a round knurled nut in the back of the Magneto. Make sure that connection is tight. If that looks good then it could be the ignition switch itself. Quote
orionflt Posted January 23, 2015 Report Posted January 23, 2015 Out of curiosity, do you keep the plane outside? and how long since you flew it last? Brian Quote
ryoder Posted January 23, 2015 Report Posted January 23, 2015 Orion, my C was sitting outside for 9 months before I bought it. Then I flew it for 25 hours and this happened to me. The switch was toast. It now sits in a hangar and flies once per week minimum. Quote
Hank Posted January 23, 2015 Report Posted January 23, 2015 I just went through this a couple of years ago. New plugs all around helped briefly, then bad starting. Did a magneto IRAN, better briefly then I was almost stranded 2 hours from home. Sent carb out for overhaul, as no matter how long I cranked or how much I pumped the throttle while cranking, never saw fuel dripping out from a flood. Still had problems, so on to the shower of sparks. For the past 2-3 years, she almost always starts right up in 2 revolutions. Ain't troubleshooting fun? Quote
Andy95W Posted January 23, 2015 Report Posted January 23, 2015 Checking the shower of sparks is pretty easy- remove #1 spark plug, go to TDC on #1 cylinder, have a friend hold your ignition switch to start (don't push so you don't engage the starter) and check for sparking to ground from the ignition lead. If no sparks, it is either the switch, p-leads, left magneto, or the shower of sparks box. The box is easy to repair. Good luck. 1 Quote
Mooneymite Posted January 23, 2015 Report Posted January 23, 2015 http://www.donmaxwell.com/publications/MAPA_TEXT/Shower%20of%20Sparks/Shower%20of%20Sparks.htm :-) Quote
rbuck Posted January 23, 2015 Author Report Posted January 23, 2015 Wow. Thanks for all of your thoughts. I'm headed back out there today to troubleshoot based on all of this. My plane's hangared, and I fly it close to every week. I don't recall hearing a buzzing, but I didn't really know to listen for it. I'll let you all know what I find, pass on any knowledge I gain. Quote
FloridaMan Posted January 23, 2015 Report Posted January 23, 2015 I'd check the left mag. When my coil went bad it was nearly impossible to get the plane to start. I think that it started due to the left mag's coil was failing intermittently. Also, to add: I also have a shower of sparks. I'm not sure on this, but I was under the impression that you don't have an impulse-couple/advance when equipped with shower of sparks. And, from here: http://www.skytecair.com/Too_Fast.htm this: A quick note regarding shower of sparks ignition systems (contributed by Scott Norsworthy Pro Aero Engines) The shower of sparks system (or buzz box, starting vibrator, SlickStart etc.) supplies interrupted DC voltage to the main and retard contact assemblies of the starting mag (usually the left) through the starting vibrator. If the aircraft voltage drops below a certain level while starting the engine the staring vibrator may stop working. Again, when the key or switch is released and the starter is no longer using most of the voltage, the engine starts and the customer is wondering what the expletive is going on. Using Sky-Tec's Troubleshooting Guide to determine the cause of the voltage drop is the best way most have found to solve this issue. If the voltage to the starting vibrator is within allowable limits then usually the starting vibrator is the culprit and should be replaced. Many of these units are the original ones supplied with the airframe and are have been overlooked at engine overhaul or replacement. (thank you, Scott!) 1 Quote
rbuck Posted January 24, 2015 Author Report Posted January 24, 2015 Well, it looks like it was nothing more than a bad connection with the wires going into the shower of sparks box. Well, that and a little embarrassment. I sure appreciated all the responses. Little things like this are really helping me learn a lot about my plane. 1 Quote
carusoam Posted January 24, 2015 Report Posted January 24, 2015 The power of MS... How else would a PP know how to identify what isn't working? Its one thing if something breaks and it makes a strange noise... (Like a Bendix drive whirrrrrr.) But, when a starter vibrator is broken, it goes silent..... -a- Quote
rbuck Posted January 25, 2015 Author Report Posted January 25, 2015 Yep, this is where I go for my trouble shooting! I have really appreciated everyone's thoughts on here, whether it was my thread or someone else's. I have learned a ton on here. Quote
carusoam Posted January 30, 2015 Report Posted January 30, 2015 Modern shower of sparks...? Go glam rock? -a- Quote
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