Power Weeder Carburetor Overflow: How to Fix Petrol Leaking from Air Filter

Petrol dripping continuously from the air filter housing or the carburetor throat is an extreme fire hazard and dilutes engine oil inside the crankcase, causing premature connecting rod failure.

Root Cause: Stuck Float Needle Valve

The carburetor needle valve regulates fuel entry. If fine rust particles from the fuel tank or sticky ethanol residue lodge between the needle and brass seat, the needle cannot seat properly. Fuel continues flowing unimpeded, filling the carburetor bowl and overflowing directly into the air intake and cylinder combustion chamber.

Field Repair & Service Protocol

1. Shut Off Fuel Cock Immediately: Prevent further fuel leakage and crankcase contamination.
2. Remove the Carburetor Float Bowl: Unscrew the central 10mm bolt at the bottom of the float bowl.
3. Inspect the Needle Valve Tip: Pull the float pivot pin. Inspect the triangular brass needle with its rubber viton tip. If the rubber tip is grooved, stiff, or pitted, replace the needle assembly.
4. Clean the Main & Pilot Jets: Clean the main jet using copper wire strands from an electrical cable. Never drill with steel pins or sewing needles, as this enlarges the micro-orifice and causes rich black smoke.
5. Install an In-Line Fuel Filter: Always splice a ₹30 transparent in-line paper fuel filter between the fuel tank and carburetor to catch rust and sediment before it hits the needle valve.