Capacitor discharge ignition system

Chrissie

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Would anyone know how to fit/where to source a Capacitor discharge ignition system to go on a Vire 12 inboard 2 stroke engine, Ive tried to google it several times but havent come up with the how and the where, just the why.
I could also do with a picture of one, as I havent a clue what it looks like.
 
Capacitive Discharge ignition can be charged either from a coil under the flywheel of the engine or from a battery.

The ignition itself can be triggered by existing points by magnetic pickup (Hall Effect device) or optical as in light beam broken by a plate with holes or similar or
In small outboards (Johnson) there is a pick up coil under the flywheel which triggers the SCR in the ignition module.

Don't discount what is effectively inductive discharge, sometimes just described as electronic ignition as used in many cars. It is in effect current through the coil which is broken or switched by a transistor triggered by any of the above.

So I imagine the old Vire has a magneto with points which break the current generated by the magnetic field in the coil.

It may be practical and a huge improvement if you have a battery and rewire to use an old car ignition coil and battery supply. If it is a twin cylinder you would need a distributor or two sets of points and 2 coils or possibly one set of points and 2 coils. It is possibly ok to generate a spark on both cylinders at once one being redundant. I am not sure about how that works with 2 strokes.

So it is all very complicated. Perhaps if you described the engine and what you want. I certainly don't think you will find a supplier of a kit for that engine. You will have to invent it.. good luck olewill
 
Why do you want to fit CDI to such a basic engine? OK the Vire magneto is not the greatest once the coils start to fail, but there are simpler ways of getting round it.

As has been suggested, use the existing contact breaker set in the mag to operate a conventional car type coil ignition system. To improve the stability of the spark you can upgrade that to a transistor assisted ignition system - available in kit form from Maplins with a Velleman Transistorised Ignition Kit - £9.99, Cat No: VE00A

The transistorised version improves matters by reducing the electrical load on the contact breaker so there is no sparking and therefore virtually no degradation of the actual electrical contact area giving a better, cleaner spark. I have fitted this to the 40 year old Albin 022 in my boat, and it has made no detectable difference to starting or running, but means the points are as still in as new condition at the end of the season - which is good as they are virtually unobtainable now!

But CDI will not improve things any further on these engines IMHO.
 
Hello,
My reason for fitting the CDI is that the Vire specialist engineer put a piece of thin metal as a shim in the flywheel to crank shaft joint, which knocked the timing right out. The engine starts to stall when the revs are put on it, the shim has been removed and the flywheel has gone away to be reground to remove the damaged areas.
It may not be possible to get out the mangled and too small woodruff key, so if the joint cant be made secure then it might need to be permanently fixed, therefore a CDI system would be the best option.
Unless anyone can think of anoher (that doesnt include throwing the engine overboard and getting a nice little diesel!)
 
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