Yo's Dad wrote:Hey Guys:
Don't forget, the heat range of the plug is more important than the brand. All the plug has to do is light the mixture. If a plug lights the fire, then that's all that is needed.
Remember, a hot plug is recommended when the engine is used very little, for a short time or may be pumping a little oil. A cooler plug is recommended for a clean burning engine that works hard for extended time periods. Sometimes you just have to experiment with different ranges to see what works best for you.
And if I don't get another chance, Merry Christmas and Happy Holidays to each of you.
This says it very well but also lets not for get that these tractors are running on a fuel that they are not built for (unleaded).
With out lead or some other retardment it burns hotter .
If you mix this with a plug that is to hot you will have preing.and that leads to holes in pistons and burnt valves and it will make the rings wear faster as it burns the oil of of the cyl. walls & we all know what happens when metal runs on metal with no lube.