---------------------------------------------------------- JabiruEngine-List Digest Archive --- Total Messages Posted Wed 07/08/15: 2 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 12:24 PM - I'm Confused (Tim Juhl) 2. 01:11 PM - Re: I'm Confused (Rob Turk) ________________________________ Message 1 _____________________________________ Time: 12:24:05 PM PST US Subject: JabiruEngine-List: I'm Confused From: "Tim Juhl" On the standard ignition modules I connected the shield side of my magneto wire to ground and the spade to the mag switch. In operation, the switch would ground the wire from the spade when off, open when operating. I have yet to run this engine but in doing some preliminary checks, I find that when I use a continuity tester on the spade that the mag switch connects to I get continuity to ground, even when nothing else is attached to it. That doesn't seem right to me so I assume I am missing something here. Hopefully one of you can enlighten me. Tim -------- ______________ CFII Champ L16A flying Zodiac XL - Jabiru 3300A Almost done! It'll fly in spring! Read this topic online here: http://forums.matronics.com/viewtopic.php?p=444573#444573 ________________________________ Message 2 _____________________________________ Time: 01:11:40 PM PST US From: Rob Turk Subject: Re: JabiruEngine-List: I'm Confused Tim, The Jabiru engine does not have 'magnetos'. It has ignition coils. The ignition coils have two windings. Both windings have one end connected to engine ground through the iron core. The high-tension (HT) winding generates the spark when a magnet on the flywheel passes the coil. The HT winding terminates in the HT lead to the distributor. The second, low-impedance winding is designed to mess up the pulse generation in the HT winding when short-circuited to ground. It makes the magnetic field collapse and prevents the energy build up for a spark. The low-impedance winding terminates in the spade. When you use an Ohm meter, you should measure about 5 - 8 kOhm between the HT lead and engine ground. You should also measure very low resistance to ground on the spade terminal. This is only 1.6 - 2.5 Ohm, so a simple continuity tester will show it as a short to ground. Download the engine maintenance manual (JEM0002-5) and find the Electrical System Specifications. It has a table showing the expected resistances for each coil type. From what you described, all is well. Rob On 7/8/2015 9:23 PM, Tim Juhl wrote: > > On the standard ignition modules I connected the shield side of my magneto wire to ground and the spade to the mag switch. In operation, the switch would ground the wire from the spade when off, open when operating. > > I have yet to run this engine but in doing some preliminary checks, I find that when I use a continuity tester on the spade that the mag switch connects to I get continuity to ground, even when nothing else is attached to it. > > That doesn't seem right to me so I assume I am missing something here. Hopefully one of you can enlighten me. > > Tim > > -------- > ______________ > CFII > Champ L16A flying > Zodiac XL - Jabiru 3300A > Almost done! It'll fly in spring! > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=444573#444573 > > ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message jabiruengine-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/JabiruEngine-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/jabiruengine-list Browse Digests http://www.matronics.com/digest/jabiruengine-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.