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Engine spark plug

Asked by: 2293 views Commercial Pilot, Flight Instructor, Private Pilot, Student Pilot

Does anyone knownwhy operating with the engine idle for prolonger time will make fouled spark plugs?

And also, why is it difficult to start engine in hot and cold weather ?

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1 Answers



  1. Robert Jankowski on Mar 11, 2016

    A rich mixture with a lower amount of heat generated will lead to plug fouling as well as oil deposits on the plug.

    Starting an engine in hot or cold weather usually is not that difficult unless we are talking about extreme heat/cold. I live in central Florida and have no issues starting aircraft engines no matter what the weather is. The POH for the aircraft should outline procedures for each condition (including pre-heat if it’s really cold) and allow you to start the engine.

    Usually the difficulty with starting the engine is in the priming phase, too little or too much fuel and you won’t achieve the stoichiometric ratio for combustion or you could flood the engine.

    Also, an experienced CFI in the area (preferably familiar with the aircraft model) would be a good source of information that isn’t found in the books on some of the idiosyncrasies of certain aircraft.

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