Craftsman Craftsman M110 140cc 21" Push Gas Lawn Mower MECH-FUEL-LEAK Error Fix: Fuel Leaking from Mower — Fire Hazard

Error code MECH-FUEL-LEAK on the Craftsman Craftsman M110 140cc 21" Push Gas Lawn Mower means: Fuel Leaking from Mower — Fire Hazard. Gasoline is visibly leaking from the push mower. This is a SERIOUS FIRE HAZARD. Stop the mower immediately, do not start it until the leak is fixed, and move the mower away from any ignition sources. Common fuel leak locations: (1) Carburetor overflow — the float needle valve in the carburetor is stuck open, allowing fuel to continuously fill the bowl and overflow. This is the most common fuel leak on small engines. Tap the carburetor bowl gently to free the stuck float. If that does not work, the carburetor needs disassembly to clean or replace the float needle and seat. (2) Fuel line — the rubber fuel lines connecting the tank to the carburetor deteriorate over time (cracking, hardening, becoming brittle). Inspect all fuel lines and replace any that are cracked, soft, or damaged. Fuel line is sold by the foot at hardware stores — match the inside diameter. (3) Fuel cap gasket — the seal in the fuel cap deteriorates and allows fuel to seep out, especially when the mower vibrates and the tank is full. Replace the cap ($5-$10). (4) Primer bulb — if the mower has a primer bulb, it can crack and leak fuel. Replace the primer bulb. (5) Fuel tank — cracks from impact, UV damage, or age. Depending on the material, the tank may be repairable with fuel-resistant epoxy or must be replaced.

The most successful fix is "Disassemble and Clean Carburetor Float Needle and Seat" (hard difficulty, ~60 minutes). Estimated DIY cost: $10-$20. HomeMD has 2 community-ranked fixes for this error.

This error is rated critical severity. It is generally not urgent and can often be resolved with a simple DIY fix.

Yes — the top-ranked community fix ("Disassemble and Clean Carburetor Float Needle and Seat") is rated hard difficulty and takes about 60 minutes. Tools needed: T25 Torx screwdriver, Carburetor cleaner spray, Small flathead screwdriver, Clean container for fuel.

DIY cost: $10-$20. Professional repair typically costs $150-$250. Many homeowners save money by trying the top-ranked community fix first.

The Craftsman Craftsman M110 140cc 21" Push Gas Lawn Mower has 8 other known error codes, including: MECH-OIL-LEAK (Engine Oil Leak or Excessive Oil Consumption), MECH-PULL-CORD (Pull Cord Breaks, Sticks, or Will Not Retract), MECH-RUNS-ROUGH (Engine Surges, Sputters, or Runs Rough), MECH-SELF-PROPEL (Self-Propel Drive Not Working or Weak), MECH-SMOKE (Engine Emits Excessive Smoke (White, Blue, or Black)), and 3 more.

Error code MECH-FUEL-LEAK also appears on 3 other Craftsman models: Craftsman B210 27cc 2-Cycle Gas Leaf Blower (210 MPH), M270 21 in 159 cc 3-in-1 Self-Propelled Gas Push Mower, S180 42cc Chainsaw. The fix may vary by model, so check each model's specific page for tailored repair steps.