How do I know if my carburetor needs adjusting?

If an engine is hard to start, barely idles, coughs, bogs, sputters or stumbles every time the throttle opens, gets horrible fuel economy, spews black carbon from the tailpipe or never seems to run very well, chances are the carburetor needs to be tuned.

What causes a rich air/fuel mixture?

Therefore, a corrupt signal indicating a colder than an actual engine will result in a rich air-fuel mixture. A faulty oxygen sensor sending the wrong signal to the engine control module can result in a rich fuel condition. Symptoms include black-colored exhaust, fouled spark plugs, and poor engine performance.

How do I know if my carburetor is too rich or lean?

Typical symptoms of a rich mixture are:

Poor fuel economy.
Sluggish acceleration.
Choke not needed from cold starts.
Sooty or black spark plugs.
Sooty or black muffler end pipes.
Strong smell of gasoline when the machine is at idle.
Uneven running (will often slow from regular idle rpms and then stop)

What happens if an engine runs too lean?

Your car will have less power than it had before. This is a result of less fuel in the ignition chamber than the car’s computer expects, and the power generated by the engine will be lower than usual. If you car is running extremely lean, you can sometimes even experience backfires, or popping when decelerating.

Is lean mixture bad for engine?

In combustion engines, “running lean” goes beyond using gas efficiently. In effect, that status makes the engine perform with less gasoline than it needs to operate properly, and it increase the amount of friction between the engine’s moving parts. Running lean can damage an engine.

What causes ash deposits on spark plugs?

Heavy ash deposits on the insulator nose resulting from oil and fuel additives, in the scavening area and on the ground electrode. The structure of the ash is loose to cinder-like. Cause: Alloying constituents, particularly from engine oil, can deposit this ash in the combustion chamber and on the spark-plug face.