laser Posted January 28, 2016 Share Posted January 28, 2016 There is normal rotation of the engine fuel flow but no ignition. After replacing ignition relay the engine start normally. But after very few engine starts the ignition relay malfuction again and there is same problem. The question is what causes the ignition relay malfuntion? It is the exciter? the drip valve? the speed sensitive control? the harness? or something else? Quote Link to comment Share on other sites More sharing options...
tinyclark Posted January 29, 2016 Share Posted January 29, 2016 I would take the ignition relay from another engine and put it on the suspect engine. Put the new relay on the other engine. This will confirm whether it is the engine, or a problem with the new relays. Quote Link to comment Share on other sites More sharing options...
pjvr99 Posted January 29, 2016 Share Posted January 29, 2016 Short in the exciter box - i get a lot of that Quote Link to comment Share on other sites More sharing options...
jack sparrow13 Posted January 29, 2016 Share Posted January 29, 2016 if the problem is the exciter.should we have ignition control CB OUT? Quote Link to comment Share on other sites More sharing options...
NATOPS1 Posted January 29, 2016 Share Posted January 29, 2016 As pvjr said you may be burning the contacts the relay uses to route power not the coil of the relay. Quote Link to comment Share on other sites More sharing options...
jack sparrow13 Posted January 29, 2016 Share Posted January 29, 2016 we replace the exciter and during first flight we have for a few seconds secondary light ON and sparking.we replace speed sense control(65 switch open), make two engine starts everything was good.Also during the replacement of SSC we saw oil at the pad of ssc and a little leak of oil at the pad of accesory.the oil leak could make ssc malfuction and affect the ignition relay or we have ssc malfuction? Quote Link to comment Share on other sites More sharing options...
pjvr99 Posted January 30, 2016 Share Posted January 30, 2016 If oil gets into the fly-weights it would most likely only affect the speed at which the switches operate; not the electrical functioning of the ignition system itself. At your next HSC, ISO or engine removal I would suggest replacing the speed switch garloc seal You would only pull the ignition cb if you had continuous ignition after engine stabilized at LSGI or NGI Quote Link to comment Share on other sites More sharing options...
jack sparrow13 Posted January 30, 2016 Share Posted January 30, 2016 Thank you pjvr99 for your interesting!The ignition relay malfuction still continous after replacement of the seal and ssc.do you have any idea? Quote Link to comment Share on other sites More sharing options...
jack sparrow13 Posted January 30, 2016 Share Posted January 30, 2016 Also we have engine vibration out of limits.what is your opinion about this? Affect the ignition relay malfuction? Quote Link to comment Share on other sites More sharing options...
pjvr99 Posted January 31, 2016 Share Posted January 31, 2016 If oil gets into the fly-weights it would most likely only affect the speed at which the switches operate; not the electrical functioning of the ignition system itself. At your next HSC, ISO or engine removal I would suggest replacing the speed switch garloc seal Quote Link to comment Share on other sites More sharing options...
pjvr99 Posted January 31, 2016 Share Posted January 31, 2016 No i do not believe engine vibration to be the cause of the ignition system problem - that is a problem all on its own. Having said that, i had an engine on the stand for vibration evaluation and found speed valve, speed switch, coordinator, gimbal assy all malfunctioning or worn out. A couple days after failing engine for out of limits vibration including turbine and RGB, I canned the excitor box for another engine. Once it was removed and I could inspect it, I found the screws holding the internal mechanism in place to have vibrated out, leaving several holes in the casing. Bottom line: vibration is NOT your friend Quote Link to comment Share on other sites More sharing options...
jack sparrow13 Posted January 31, 2016 Share Posted January 31, 2016 Thank's pjvr99. Quote Link to comment Share on other sites More sharing options...
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