# Lawn Boy



## Jags (Dec 21, 2007)

I have a Lawn Boy Mower that will not start. It has no spark. I bypassed the safty switch and had the coil tested, they said it was good but it all points to the coil......helppppppppppp
thanks in advance 
jags


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## octaneman (May 13, 2009)

Using a DVOM make sure you got continuity on the wires leading to the primary side of the coil. If it turns out ok you may have to test the magneto. To do this you have to know what it looks like : The magneto, like the ignition coil on an automobile, contains two windings: 

A primary with a few turns of heavy wire. 

A high voltage secondary with thousands of turns of super fine wire. 

To test the magneto:

Primary (if non-electronic and accessible): very low - guessing less than an ohm.
The secondary will always be accessible for testing but the primary of an electronic ignition may be not be due to the electronic components: 
Secondary: 3 K ohms (maybe a little higher but not open). Much lower would indicate a shorted winding. 

Wires can break due to corrosion or vibration. This would result in an open winding - infinite resistance. Shorts can develop between adjacent windings or to the core. This may be detectable as reduced resistance but without knowing exactly what it should be, there is no way of knowing if a slight discrepancy represents a problem or just slight variations in design or manufacturing.


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## k2skier (Sep 30, 2008)

Electronic ignition magnetos cannot be tested with a VOA meter because all the windings, including the trigger coil, have a common ground. The only test is to remove the shorting wire, (the small kill wire) reinstall the starter, (can't hand spin to test) and retest spark, if it has spark it's in the kill circuit, if it doesn't have spark ignition module, (coil) is bad.


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