Hot Plugs

[Goraidh (Jeff)]

Hey Guys, What are the symptoms of running plugs that are too hot for a working tractor? What damage can/will that do in the long haul? Short haul?

Thanks,
Jeff

 

[Rick Spivey]

Here's a good diagnosis chart.

http://www.aa1car.com/library/reading_spark_plugs.jpg

 

[Eugene]

http://www.spark-plugs.co.uk/pages/tech ... gnosis.htm

Above is a nice pictoral on spark plugs and related problems.

Wrong heat range, shorter plug life and poor engine performance near end of the spark plugs life.

 

[Goraidh (Jeff)]

Thanks for the links, guys. Eugene, you say "poor performance at end of plug's life." But do/will they do damage to valves or heads or cylinders or pistons or rings? I'm running Autolite 386s in my working Cub, which should be just fine, but the PO had hotter plugs installed when I bought the Cub earlier this year and ran them for a while before changing them out. I'm just wondering if there's anything I should be aware of or keep my eye on.

Thanks again,
Jeff

 

[Eugene]

No resulting damage to the engine. General idea is to get or adjust the spark plugs heat range to burn off deposits accumulated during your engines operation or the way you operate your engine.

Hot or cold plugs referes to the spark plugs ability to conduct heat away from the inner tip of the cermanic insulator.

 

[Goraidh (Jeff)]

Thanks, Eugene. A great help.

Jeff