Excess fuel consumption
- Unnecessarily frequent use of the gas pedal
- Frequent short distance driving (engine fails to warm up)
- fuel leak
- Air filter clogged Incorrect suction adjustment
- Incorrect use of suction
- Float top position incorrectly set or needle valve defective
- Severe carburetor wear
- Excessive carbon buildup in the cylinder head
- Severe engine wear
Cold starting problems
- Suction misadjusted
- Float top position incorrectly set
- Air leaking into the intake manifold or carburetor
Hot engine starting problems
- Air filter clogged
- Suction misadjusted
- Float top position incorrectly set or needle valve defective
- Steam lock in the fuel line (especially often in hot weather or at high elevations above sea level)
"Clap" in the exhaust system
- Air leakage into manifold (collectors) or exhaust system
- Too lean mixture
- Incorrectly adjusted valve clearances or burnt exhaust valve (valves)
- Valve timing incorrectly adjusted (after engine overhaul)
- Incorrectly adjusted ignition timing or other malfunctions of the ignition system
Ejection of the mixture from the carburetor neck
- Incorrectly adjusted valve clearances or burnt intake valve (valves)
- Too lean mixture
- Valve timing incorrectly adjusted (after engine overhaul)
- Incorrectly adjusted ignition timing or other malfunctions of the ignition system
Poor fuel supply to the carburetor
- Fuel tank empty
- Clogged fuel tank vent pipe
- Clogged fuel line
- Leak on the suction side of the pump (there are air bubbles in the pumped fuel)
- Faulty fuel pump or clogged filter
- Clogged carburetor inlet filter