---------------------------------------------------------- RotaxEngines-List Digest Archive --- Total Messages Posted Thu 05/22/14: 3 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 01:07 PM - Uneven Mag Drop 912 ULS (JohnF) 2. 02:26 PM - Re: Uneven Mag Drop 912 ULS (Roger Lee) 3. 03:22 PM - Re: Uneven Mag Drop 912 ULS (JohnF) ________________________________ Message 1 _____________________________________ Time: 01:07:49 PM PST US Subject: RotaxEngines-List: Uneven Mag Drop 912 ULS From: "JohnF" This looks like a case of "It was working until I fixed it" Annual condition inspection; new plugs at 0.027-inches, carbmate showed exact balance, Dyna Vibe gave engine smoothness like a turbine, cylinder differential pressure almost perfect all cylinders, began using non-ethanol 91-octane gas, no oil consumption, crossover fittings (hoses) all tight, cruise speed normal, climb out at max throttle 5,000+ then over 5,100 after a few moments while still over the runway. Spark plug wires firmly attached "Killing" A side ignition, mag drop averages 150 rpm "Killing" B side ignition, mag drop averages 290 rpm, so it looks like a problem with the A side ignition. Next try will be new plugs (again) on top of cyl #1 & 2 new plugs (again) on bottom of cyl #4 & 3 to eliminate a bad new plug. Anything else to check? Read this topic online here: http://forums.matronics.com/viewtopic.php?p=423608#423608 ________________________________ Message 2 _____________________________________ Time: 02:26:13 PM PST US Subject: RotaxEngines-List: Re: Uneven Mag Drop 912 ULS From: "Roger Lee" What rpm are you doing the mag drop at? Plugs are worth checking / replacing and gaps. Since you pulled the plug boots off you may have inadvertently pulled the plug wire a little too much where it goes into the boot. It wouldn't hurt to unscrew each one and trim the wire back 1/4" and then thread the boot back on. I even think 150 is a little high if the rpm is 3500 and under. Average is 50-100. -------- Roger Lee Tucson, Az. Light Sport Repairman - Maintenance Rated Rotax Repair Center - Heavy Maint. Rated Home 520-574-1080 TRY HOME FIRST Cell 520-349-7056 Read this topic online here: http://forums.matronics.com/viewtopic.php?p=423611#423611 ________________________________ Message 3 _____________________________________ Time: 03:22:21 PM PST US Subject: RotaxEngines-List: Re: Uneven Mag Drop 912 ULS From: "JohnF" Roger, I run up to 4,000 rpm and then 'kill' each circuit in turn. I have never 'unscrewed' a plug boot...I assume I can hold the main wire and twist on the 'plug' end that would connect to the top of the spark plug. I am picking up 4 new plugs tomorrow and will gap and install...will try that plug wire trimming and reattaching. Thanks for the input Roger...I wish you were a bit closer, I would just fly down to Tuscon and put the whole thing into your hands ! John Read this topic online here: http://forums.matronics.com/viewtopic.php?p=423614#423614 ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message rotaxengines-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/RotaxEngines-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/rotaxengines-list Browse Digests http://www.matronics.com/digest/rotaxengines-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.