The answer from barnyard is correct. If it is fouling plugs, especially if only one cylinder, putting a full set in it may cause detonation that can take out the pistons. If it is getting loader work, or parades, it would be OK. If you are running 87 octane 10% ethanol, running premium will also curb knock. Jim
 
in champion and autolite the higher the # the hotter the plug. d21 is hotter than d16. plus when you look at the plugs the electrode on a hotter plug will be thinner. plus there is the longer reach ones also, which is the 15y I believe.the harder you work the engine the colder plug you would go , to reason.
 

We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today.

Back
Top