qcowboy Posted February 13, 2009 Report Share Posted February 13, 2009 My TL320 was running great one day, and the next, it wouldn't start. I suspected a bad condensor, since they tend to die suddenly. So I installed a new condensor, and new points as long I was already inside the flywheel. Sadly, still no spark. So I'm down to either a stator that produces no power, or a bad coil. Presumably, I should be able to kick the bike over with a meter attached to the blue wire that feeds the coil, and measure (pulsating) power there. right? If there is no power, then I have a bad stator (or a shorted/ broken wire) If I have power there, but still no spark, then my coil is bad, correct? Thanks for all the help, gang! I'm looking forward to some riding soon. I have a trip to Moab planned for late March, and my indoor arena should be finished soon, so I can do some practice drills at home in winter. Quote Link to comment Share on other sites More sharing options...
stork955 Posted February 13, 2009 Report Share Posted February 13, 2009 Gday, with the points open and condenser disconnected check resistance of the stator (source coil). You should see a small resistance but not open or zero and no circuit to ground. With the points closed you should see very low resistance to ground. this will check that side of things. For an output test you should see around 50 or more volts AC kicking. Coil tests - primary will be around 2- 6 ohms, not open or zero, secondary significantly more, around 3k - 6k ohms, not zero or open with the plug cap removed. Check the plug cap seperately, if a resistor type the value is on the side, around 5k ohms generally otherwise zero. HTH, Cheers, Stork. Quote Link to comment Share on other sites More sharing options...
qcowboy Posted February 17, 2009 Author Report Share Posted February 17, 2009 Thanks, Stork. Help me understand the wiring diagram, if you would. Here's a link to the only wiring diagram I have, and it is woefully incomplete in the area of the stator plate. http://www.trialscentral.com/forums/upload...-1230650968.jpg There are three separate windings on the stator plate. One is for the lighting circuit, and has yellow and yellow/green wires at each end of the winding. Since I have no lights, the yellow wires are not connected to anything. They are just insulated and hidden inside the harness. The other side of the stator plate has two windings, stacked on top of each other. In the rear is the winding that provides power to the ignition circuit. One end of this winding is grounded, and the other has a black wire that feeds power to the points/condensor, then on to the ignition coil. The third winding is a mystery to me. It has green wires coming from each end. On my bike, they are not connected to anything. The wiring diagram does not indicate where those green wires should be connected. Can anyone help me? Thanks, Ted Quote Link to comment Share on other sites More sharing options...
pedronicman Posted February 17, 2009 Report Share Posted February 17, 2009 On my TL 320 i run the black wire from the ignition coil only up under the tank where i have mounted the condensor. The larger L/H lighting coil has the wire cut completely off and the same on the front R/H coil also- so these are redundant , but you must leve these coils bolted on for the flywheel to work fully hope this helps Quote Link to comment Share on other sites More sharing options...
qcowboy Posted February 17, 2009 Author Report Share Posted February 17, 2009 So if I have two redundant coils on the stator plate, and one that I suspect is bad, can I connect one of the redundant coils to my ignition system (temporarily) to test whether the REST of my ignition system is working correctly? I notice, of course, that the two redundant coils are both larger, so I assume they produce more power. Would I risk damage to my ignition coil/condensor if I were to use one of the redundant coils to test them? Quote Link to comment Share on other sites More sharing options...
pedronicman Posted February 17, 2009 Report Share Posted February 17, 2009 Sorry i am not a wiz with electrics that much , i just did the simple job of doing away with the wires i did not need. You would probably be better speaking to 'The Rotax man' - Peter Knight- very helpful man- www.rotax.co.uk 01761 414106 If it helps the L/T coil and H/T coil and all Bosch ignition parts are still available new -from Rotax. Hope this helps. Quote Link to comment Share on other sites More sharing options...
qcowboy Posted February 20, 2009 Author Report Share Posted February 20, 2009 Well, problem solved. Now that I've solved the problem, I feel ashamed at the silly logic in my original post. I jumped to expensive conclusions, without first eliminating the cheap ones. I went out to the garage tonight and pulled the stator winding that drives the ignition system. I tried Stork's tests with the ohmmeter, and found a slight resistance through the winding, as he predicted (very slight, though. Only .5 to 1 ohm, which would be nearly undetectable without carefully zeroing the meter to start.) I decided to replace the insulated lead from the winding before re-installing it, just in case there was deterioration inside the insulation. With the new lead soldered in place, and the winding re-installed, I re-installed the flywheel. I tried kicking the engine over, with the spark plug lying on the head, but got no spark. I attached the meter to the output from the stator winding, and measured some inconsistent voltage when I kicked the engine over. I plugged the output back into the coil. I wondered if the ground strap from frame to head was loose, so I tightened it, and immediately broke off the ring fitting on the end of the strap. I tried holding the spark plug next to the frame, and kicking over the engine. What are the odds that you WILL get a spark the instant you hold the business end of the coil wire in your hand? Good odds! I didn't see the spark, but I sure felt it. (foreshadowing) So I knew the stator was feeding the coil, and that the coil was creating a spark when I used the frame as a ground for the plug. So I fixed the ground strap to the same frame lug where I had shocked myself, and tried laying the spark plug back on the head. I kicked her over, and . . . no spark. Damn! So I began to wonder whether I had a bad plug wire. I dug into my parts stash and found a newish looking length of silicone plug wire left over from one of my Fiats. I rigged it with proper fittings to install on the bike, and tried again to kick the bike over with the plug lying on the head. Still no spark. So I tried again holding the plug to the frame, and kicked it over. OUCH! FAT BLUE SPARK. I could feel the blue, even if I didn't see it. And the wheels began to turn in my head. (none too soon, of course) why could I feel a spark when I held the plug in my hand, but not see it when the plug was lying on the head? Because the spark I felt was coming through the wire, not the plug. The plug was bad. Obvious, right? Back to the stash of Fiat parts, and I found a plug that would fit the bike. I laid it on the head. Fat Blue Spark. Dunce. Plug in its place, tank back on the bike . . . starts right up. First kick. I just wasted several cold evenings in the garage fighting with a problem I should have been able to diagnose in five minutes. On the upside, I learned the entire SWM wiring diagram by heart, and replaced the points and condensor, which gives me some peace of mind. Now on to my next question: what plugs should I buy to replace the bad plug? While the Fiat plug fits, and the bike runs, I don't have any idea whether it is near the correct heat range, so I'm not inclined to ride the bike much with the Fiat plug in place. (at least it's Italian!) Quote Link to comment Share on other sites More sharing options...
martinm Posted February 20, 2009 Report Share Posted February 20, 2009 The correct plug is an NGK BP5ES Martin Quote Link to comment Share on other sites More sharing options...
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