So this will be the first time ever that I disagree with Lynn.While there is no doubt that the plugs he recommends may be the best, I do not use them. Those plugs are $40 each. I use the NGK BR10EIX plugs which are iridium and almost as cool, but most importantly only cost $10. From my pocket book, good enough is good enough. While I do have high duty cycle, I don't have the peak stresses that racers incur, even in my turbo engine. I find that the iridium plugs last significantly longer and as far as I can tell they are not overheating and are producing great spark.. I tried the plugs that Lynn recommend but they only last 20 hours or so while the iridiums last in excess of 50 hours. So every 100 flight hours the cost difference is over $750! and I cant tell difference in the way my engine runs.Steve, I'm sorry that I cant solve your problem, but I am pretty sure the problem is not the spark plugs.Dave LeonardTurbo Rotary RV-6On Fri, Aug 12, 2016 at 4:17 PM, Stephen Izett <flyrotary@lancaironline.net> wrote:Thanks LynnIll look to get these plugs.One thing that has changed is I’m now reading very low to zero coolant pressure.Not sure if its the sender or something else. I’ll check it in a few weeks then I can get back to the hangar.If a rotary looses coolant or pressure what are the reasons this can happening?SteveOn 13 Aug 2016, at 2:50 AM, Lehanover <flyrotary@lancaironline.net> wrote: I recommend the NGK R6725-11.5 spark plug for 100% duty cycle operation. Gapped at .010" to .012". Race car settings. There you go...............rotary talk. Lynn E. Hanover This is what I would do. Get all of your tuning done on the ground and or, just above a long runway. Install a heated oxygen sensor, Plug heat ranges in the 10s are for heavy street use. Not used (or should not be used, my opinion) for a 100% duty cycle as in aircraft. If 10s cured your problem you have already demonstrated to yourself the problems of a too hot a (high heat range) plug. Once the tip of the plug is overheated you have lost control of your ignition timing. This is a very bad idea. Followed by preignition and or, detonation. Both can lead to severe engine damage. Once your testing is complete and long flights are next, I would remove and discard the stationary gears and magnaflux the rotor gears. You can check all of the engine parts at that time. The NGK R6725-11.5 plug is gifted to most competitive race teams by Mazda. Know what your timing actually is. Mark your flywheel teeth with colored paint. Easy to see and very accurate. Lynn E. Hanover<Racerpic.jpg>--Homepage: http://www.flyrotary.com/Archive and UnSub: http://mail.lancaironline.net:81/lists/flyrotary/List.html
Thanks LynnIll look to get these plugs.One thing that has changed is I’m now reading very low to zero coolant pressure.Not sure if its the sender or something else. I’ll check it in a few weeks then I can get back to the hangar.If a rotary looses coolant or pressure what are the reasons this can happening?SteveOn 13 Aug 2016, at 2:50 AM, Lehanover <flyrotary@lancaironline.net> wrote: I recommend the NGK R6725-11.5 spark plug for 100% duty cycle operation. Gapped at .010" to .012". Race car settings. There you go...............rotary talk. Lynn E. Hanover This is what I would do. Get all of your tuning done on the ground and or, just above a long runway. Install a heated oxygen sensor, Plug heat ranges in the 10s are for heavy street use. Not used (or should not be used, my opinion) for a 100% duty cycle as in aircraft. If 10s cured your problem you have already demonstrated to yourself the problems of a too hot a (high heat range) plug. Once the tip of the plug is overheated you have lost control of your ignition timing. This is a very bad idea. Followed by preignition and or, detonation. Both can lead to severe engine damage. Once your testing is complete and long flights are next, I would remove and discard the stationary gears and magnaflux the rotor gears. You can check all of the engine parts at that time. The NGK R6725-11.5 plug is gifted to most competitive race teams by Mazda. Know what your timing actually is. Mark your flywheel teeth with colored paint. Easy to see and very accurate. Lynn E. Hanover<Racerpic.jpg>--Homepage: http://www.flyrotary.com/Archive and UnSub: http://mail.lancaironline.net:81/lists/flyrotary/List.html
On 13 Aug 2016, at 2:50 AM, Lehanover <flyrotary@lancaironline.net> wrote: I recommend the NGK R6725-11.5 spark plug for 100% duty cycle operation. Gapped at .010" to .012". Race car settings. There you go...............rotary talk. Lynn E. Hanover This is what I would do. Get all of your tuning done on the ground and or, just above a long runway. Install a heated oxygen sensor, Plug heat ranges in the 10s are for heavy street use. Not used (or should not be used, my opinion) for a 100% duty cycle as in aircraft. If 10s cured your problem you have already demonstrated to yourself the problems of a too hot a (high heat range) plug. Once the tip of the plug is overheated you have lost control of your ignition timing. This is a very bad idea. Followed by preignition and or, detonation. Both can lead to severe engine damage. Once your testing is complete and long flights are next, I would remove and discard the stationary gears and magnaflux the rotor gears. You can check all of the engine parts at that time. The NGK R6725-11.5 plug is gifted to most competitive race teams by Mazda. Know what your timing actually is. Mark your flywheel teeth with colored paint. Easy to see and very accurate. Lynn E. Hanover<Racerpic.jpg>--Homepage: http://www.flyrotary.com/Archive and UnSub: http://mail.lancaironline.net:81/lists/flyrotary/List.html