Can anyone explain the Ignition system of piston engine in detail?
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Joined: May 2013
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From: India
Can anyone explain the Ignition system of piston engine in detail?
I get confused everytime about the magneto circuit.
What happens when the ignition switch is placed in the ON position?
What is impulse starter?
What happens when the ignition switch is placed in the ON position?
What is impulse starter?

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From: turn L @ Taupo, just past the Niagra Falls...

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From: All at sea
The ignition switch allows the magneto to do its bit towards the 'bang' part of the 'suck, squeeze, bang, blow' cycle. The impulse starter - well you guessed it - helps start the sucker in the first place. What may be confusing you is that it is not a separate starter motor at all, but a part of one (or sometimes both) the magnetos. Starting assist may also sometimes be referred to as a 'shower of sparks' ignition.
The really, really important thing to know about the ignition switch on a magneto-spark engine is that OFF may not really be OFF. If the grounding (or earth) is not secure the magneto will still be 'live' after you shut the engine down on the mixture. Which is why you do a dead-cut check prior to shutdown (I hope).
As Saigon says, all of this in much better detail can be found by googling. Google will give it to you as scientifically, or as basically, as you want.
The really, really important thing to know about the ignition switch on a magneto-spark engine is that OFF may not really be OFF. If the grounding (or earth) is not secure the magneto will still be 'live' after you shut the engine down on the mixture. Which is why you do a dead-cut check prior to shutdown (I hope).
As Saigon says, all of this in much better detail can be found by googling. Google will give it to you as scientifically, or as basically, as you want.
Last edited by Mach E Avelli; 13th May 2013 at 07:10.




