1996 - No Spark

[Kirk Jurinek]

Put it away in the fall and pulled it out today. No spark. I assume I need to take the pull start off, flywheel and clean the magnets and pick ups. Does the 1996 still have points?

Thanks in advance for any help.

Kirk

[Jonn]

1981 was the last year that points were used in Kitty Cats. Everything from 1985 and newer do not have points.

[Amos]

So what provides spark on a KC if it don't have points? ? ? ?

[MachJeff]

The question is what keeps it from sparking. Seeing as it is post-storage, I'd look for corroded connectors. There is a coil behind the flyweel that makes the electricity for the spark, then it runs through wires to the CDI box. From there the plug wire goes to the spark plug. Check all connections and try a new plug. Use a test light to check for power coming from the coil. There could also be a bad connection in the kill switch or ignition wiring that has it basically 'turned off'.

[Amos]

Is a CDI BOX like a MAGNEITO or am I way off base here. And what does CDI stand for? ?

[Jonn]

CDI stands for Capacitive Discharge Ignition.

In the simpliest of terms, the Kitty Cat ignition works through a simplistic CDI design. The primary coil located on the stator plate (inside the flywheel) has wire windings on it and magnetic pickups. The flywheel has a magnet mounted on the inside of it. As the flywheel spins, the magnet pulls across the coil magnetic pickups and creats a low voltage electric pulse. At a precise instant that pulse is sent to the seconary coil where the electric current is split between two sets of wire windings. Then there is a reaction that increases the electric spark which is then sent up the plug wire to the spark plug.

Although a little confusing, that's the short explanation. The long explanation regarding timing, effects on wire windings and so on is way too long to cover on this forum. But I think that gives you an idea of how it works. I'm sure if there is an electrical engineer on the forum he/she could give you a much clearer explanation.

[Engineer]

Pretty close Jonn and good enough for the forum. I’m an ME not an EE but the short explanation is as follows. As the magnet on the flywheel passes by the core of the stator plate it induces a current like an electric motor but backwards (i.e. a generator). This low voltage / high current electrical pulse then energizes the ignition coil. The ignition coil has primary and a secondary winding. The primary is a low number of turns and is connected to the stator. The secondary windings are much smaller wire with a lot of turns. The ratio of primary to secondary turns controls the voltage of the secondary winding. The coils are inductors and inductors try to keep things at a steady state. They initially resist a current change and then will try to keep the current flowing after the power source is removed. In mechanical terms, they are the flywheel of electronics. As the current pass through the primary windings, it creates a magnetic field (stored energy). When you break the primary circuit the magnetic field collapses. That energy has to go some where and collapses into the secondary windings. Because there are more secondary turns, the voltage will be higher but the current will be lower. The higher voltage is what gives you the spark at the sparkplug. Timing of the breaking of the primary circuit is your spark timing. I know this was much more than you ever wanted to know but thanks for reading.

[Jonn]

That was perfect! I knew I couldn't have said all of that in less than eight pages without confusing the heck out of everyone. That was short, to the point, and understandable. Thanks for helping me out!!!

[Engineer]

I just hope I didn't confuse anyone.

Jonn
One of these days I'll have to get up there and see your shop.

[MachJeff]

And to answer Amos' question simply, the CDI is NOT like the magneto. The magnets and windings are still behind the flywheel, and there is still a secondary (aka ignition) coil. The CDI basically does the job of the points, but with an electronic circuit board instead of mechanically.

Mind you that is the way I was lead to understand it, and I am not offended by being corrected.

[Amos]

You guy's are simpley AWESOME. Again this is the one of the greatest websites EVER. Thanks for the GREAT answers! MERRY CHRISTMAS Kitty Cat Fanatics.