Reading spark plugs
(Changed affect to effect since it was a noun) |
(Amended picture description to alleviate confusion between detonation and pre-ignition and to provide the correct remedy for the problem.) |
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[[File:Rich18.jpg]] | [[File:Rich18.jpg]] | ||
− | Black or brown | + | Black or brown specks: This is an indication of detonation which is caused by ignition timing that is too advanced for the air/fuel ratio or octane of the fuel. Detonation (an undesirable, uncontrolled combustion of the air/fuel mixture after the ignition event) causes the boundary layer of air within the cylinder to be disrupted, which in turn causes the components and surfaces within the cylinder to absorb heat from the combustion process and increase in temperature. The black spots are the result of oil deposits bypassing the piston rings during detonation and being fused onto the porcelain by the increased cylinder temperatures. Tiny beads of grey/silver material apparent on the porcelain are melted piston. Reduce the ignition timing, richen the mixture, increase the octane of the fuel or a combination of all of these to prevent this situation. |
− | The black spots are the result of | + | |
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{{Warning}}Do not underestimate the damage this condition can cause your engine. Correct this by whatever means necessary. | {{Warning}}Do not underestimate the damage this condition can cause your engine. Correct this by whatever means necessary. | ||