:
Unscrew the main jet and the pilot (idle) jet. Spray both jets with aerosol carburetor cleaner. Verify you can see light through the center orifices.
The 152FMH is typically paired with a . Performance issues are almost always caused by clogged internal jets. Standard Carburetor Settings Pilot Jet (Idle Jet): #32 - #35 Main Jet: #75 - #82 152fmh engine service manual
Disassemble the carburetor, remove the pilot and main jets, and clean them with carburetor cleaner and compressed air.
Ensure the engine is on the . Both rocker arms should have slight play. If they are tight, rotate the flywheel one full 360-degree turn back to the "T" mark. Measure Clearance: Remove the intake (top) and exhaust (bottom) valve covers. : Unscrew the main jet and the pilot (idle) jet
The 152FMH typically utilizes a Sheng Wey or PZ19 clone carburetor. Fuel varnishing from stagnant petrol causes most running issues.
| Specification | Value | Source | |---|---|---| | | Single-cylinder, 4-stroke, air-cooled | | | Displacement | 107cc – 110cc | | | Bore × Stroke | 52.4mm × 49.5mm | | | Compression Ratio | 8.6:1 – 9.1:1 | | | Max Power | ~4.9 kW – 5.0 kW @ 7500-8000 rpm | | | Max Torque | 6.6 – 7.5 N·m @ 5500-6000 rpm | | | Idle Speed | 1500 rpm (±150 rpm) | | | Ignition System | CDI (Capacitor Discharge Ignition) | | | Lubrication | Pressure / splash type | | | Cooling | Forced air-cooled | | | Fuel System | Carburetor (Piston-type) | | | Transmission | 4-speed (1-down, 3-up), manual or automatic clutch | | The 152FMH is typically paired with a
When reassembling, clean all gasket surfaces thoroughly. Use a cross pattern to tighten fasteners incrementally: 12–14 N·m (9–10 lb-ft) Cam Sprocket Bolts (M5): 9 N·m (7 lb-ft) Cylinder Head Side Bolts (M6): 10 N·m (7.5 lb-ft) 6. Electrical System & Troubleshooting
110Ω – 140Ω (Blue/White wire to ground) Ignition Coil Primary Resistance: 0.4Ω – 0.6Ω Common 5-Pin CDI Pinout Guide
Stuff a clean rag into the open crankcase mouth to prevent loose parts from falling inside. Remove one of the piston pin circlips using needle-nose pliers. Push the wrist pin out and remove the piston. Inspection and Reassembly
Whether you are performing routine maintenance or undertaking a complete top-end rebuild, this comprehensive service guide provides the technical specifications, step-by-step procedures, and troubleshooting steps required to keep your 152FMH engine running flawlessly. 1. Engine Specifications & Identification