There may be more fuel going through the combustion chamber than the spark plug can ignite. The excess fuel seeps through the (main or head) gasket and into the oil sump. You should check the compression with a compression checker in line with the spark plug and the condition of the spark plug, the carburetor setting, the operation of the choke, or even the condition of the air filter.
it is under the flywheel
if it only backfires when shutting off, usually this means its getting to much gas!! if it backfires will running adjust carburater.
The float is probably stuck open.
no, but there is an inline filter.
It has to go throught the carb. Typically this is caused by a bad float. You will need to remove the carb and clean it or replace it.
If it is an older vehicle with a mechanical fuel pump-- diaphram could be torn allowing gas to be pumped directly into engine
change your fuel filter and check to make sure that nothing is obstructing the gas flow in your gas lines. you will have to drain the gas out of the tank. so have a gas can there to catch the gas. that stuff costs as much as gold these days. ain't that a B !
Either the Carbourator (older cars) or the ECU (fuel injected)
Does it have spark?, Compression? Timing?
check engine light on,getting poor gas mileage on 1996 Plymouth neon
Not really sure what you're getting at. If your lawnmower engine is a 2-stroke then you need a mixture of oil and gas to run it.
gas might not be getting to the engine why the question so vague?