Problem: Unable to Reduce Engine RPM to Slow Idle
Chipped or broken reeds on reed block.
Problem: Rough Idle
Excessive preload on reeds.
Problem: Engine Runs Too Lean
Carburetor is loose. Air leaks past mixing chamber cover. Tighten bolts securely. Tighten cover or replace gasket.
Fuel level is too low. Reset float level.
Clogged high speed jet. Inspect jet for varnish or debris and clean.
Restricted fuel flow to carburetor. Check fuel lines and filters for restricted flow.
Incorrect high speed jet. Refer to main jet chart and replace with proper jet.
Idle mixture set too lean. Adjust to run richer. Turn idle mix screw counterclockwise.
Air leakage into fuel system. Inspect fuel line connections, hose clamps, fuel pump and fuel outlet tube (located in fuel tank) for loose fittings.
Anti-siphon valve restricting fuel flow. Inspect valve and/or test engine without valve in fuel system.