Engine Does Not Start Or Is Hard To Start - Honda Metropolitan CHF50 Service Manual

TROUBLESHOOTING
ENGINE DOES NOT START OR IS HARD TO START
1. Carburetor Inspection
Check the fuel flow to the carburetor.
Is fuel reaching the carburetor?
NO - • Clogged fuel hose or fuel filter
• Sticking float valve
• Clogged fuel cap breather
• Faulty fuel pump
• Loose or disconnected fuel pump system wire
YES - GO TO STEP 2.
2. Spark Test
Perform spark test.
Is the spark good?
NO - • Faulty spark plug
• Fouled spark plug
• Faulty ECM
• Broken or shorted spark plug wire
• Broken or shorted ignition coil
• Faulty ignition switch
• Faulty ignition pulse generator
• Faulty engine stop switch
• Loose or disconnected ignition system wires
YES - GO TO STEP 3.
3. Cylinder Compression Inspection
Test the cylinder compression.
Is the compression within specification?
IMO - • Valve stuck open
• Worn cylinder and piston rings
• Seized valve
• Improper valve timing
YES - GO TO STEP 4.
4. Engine Start Condition
Start by following the normal procedure.
Does the engine start but then stops?
YES - • Carburetor incorrectly adjusted
Intake manifold leaking
Improper ignition timing (faulty ECM or ignition pulse generator)
Contaminated fuel
Faulty starting enrichment (SE) valve
NO - GO TO STEP 5.
5. Spark Plug Inspection
Remove and inspect the spark plug.
Is the sparkplug in good condition?
NO -
YES -
Flooded carburetor
Faulty starting enrichment (SE) valve
Throttle valve open
Air cleaner dirty
Incorrect spark plug gap
Incorrect spark plug heat range
Improper ignition timing
Poor adjustment valve clearance
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