It has long been believed that if you drill the side electrode of a spark plug with a thin drill, the spark will intensify. In this way, old worn out candles are reanimated, and really make them spark better. Why it works, and is it worth it.
The process of refining candles and their real check
To improve it, you need to adjust the gap on the candles, and drill its side electrode in the center with a 1 mm drill. After that, it will start to work better.
To check the effectiveness of the modernization, a special device is used that simulates the conditions in the engine cylinder, namely, creates high pressure.
In atmospheric conditions, candles almost always work well, but at high pressure they begin to pierce. The tested plug worked without failures under conditions up to 16 atm before revision. Immediately after drilling, it easily overcomes this threshold and withstands much more.
All this is due to the formation of metal burrs on the back of the electrode after drilling. It is worth removing them, and the candle stops working correctly again when the pressure rises to 16 atm.
Thus, the improvement from reworking the plugs is observed for a short time until the burrs are burned out. In fact, the theory of increasing engine power after drilling the side electrode turns out to be untenable. Its trimming does not work either.
It is best to simply change the candles according to the replacement regulations.
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