carbon fouled??

[trikes4life]

What causes carbon fouled plugs.

[TeamGeek6]

All carbon in the cylinder comes from gas and/or oil that does not burn. Gasoline is a "hydrocarbon" (made of hydrogen and carbon) and that needs oxygen to burn. Lack of oxygen usually leaves un-combined carbon, and that gets deposited on the cylinder and spark plug. Depends on the source, in a 4 stroke, unburned fuel or leaky rings or valve guides. IN a 2 stroke, unburned premix. Excess fuel looks different than excess oil, oil deposits are usually soft.

almost everyone immediately blames carburetor, but overlook the ignition, because thats the part that few folk understand.

In the old 1938 Chevy I restored this Summer, there was absolutely nothing wrong with the engine or carb, but the plugs were still black. I installed a set of long reach plugs and it runs absolutely perfectly on the stock jetting.