Editing Reading spark plugs (section)
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===Areas of the plug to inspect=== *The ground strap will show a color change in two spots on the 90 degree bend **The first mark furthest from the plug body shows the '''initial''' (or base) timing **The second indicates '''total''' timing {{Warning}}If the second mark is all the way to the base of the ground strap where it attaches to the plug body, this is a sign the plug got too hot. An ideal 'safe' timing range is when the total timing discoloring is located just past the bend. [[File:Timing indicator mark1.jpg]] Next, inspect the threaded area for the heat range. The threads will show a dull burnt-looking color change, 2-3 threads is ideal. *To increase the number of burnt threads, increase the heat range of the plug *If you have 4-5-6 threads burnt you need to get a colder plug [[File:Heat range2.jpg]] <br> Indicators for the air/fuel ratio can be found in two spots, one spot known as the '''''air/fuel ring'''''. On the air/fuel ring, you're looking for a complete 'full turn' of discoloration. Ideally this should be lightly colored soot. As the fuel ring soot darkens, this indicates a richer air/fuel ratio. If you're tuning the engine for maximum horsepower, the ring should be very light and not make a full circle around the ring.<br> {{Warning}}Use caution when approaching a borderline too-lean condition. A ''little'' lean can make good power, but being '''too''' lean can melt a piston. [[File:Air fuel ring3.jpg]] The second place to inspect for the air/fuel ratio is the the porcelain. Being too rich leaves light to dark color rings on the porcelain. Ideal conditions leaves the porcelain like new to shiny white. <br> {{Warning}}Beware of grayish or peppery speckles as this is most likely molten piston material being deposited on the porcelain. The cause of this has to be corrected immediately.
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