© Honda Motor Co., Ltd. Power Product Service Division.

GX240/GX270/GX340/GX390A1 SIZE 841×594 ENG

3.5 kgf‧m,25lbf‧ft

2.4 kgf‧m,17lbf‧ft

1.0 kgf‧m,7lbf‧ft

2.4 kgf‧m,17lbf‧ft

7.5 kgf‧m,54lbf‧ft

2.3 kgf‧m,17lbf‧ft

1.4 kgf‧m,10lbf‧ft

2.4 kgf‧m,17lbf‧ft

Rotate the governor arm shaft as far as it will go in the same direction the governor arm moved to open the throttle.Tighten the nut on the governor arm.

Align the punch marks on the balancer and balancer drive gear (larger gear on the crankshaft).

Align the punch marks on the camshaft and timing gear(smaller gear on the crankshaft).

Maximum speed 3.850±150min-1(rpm)

Specified clearance 0.4± 0.2mm(0.016±0.008 in)

THROTTLE LEVER LIMITING SCREW

GOVERNORARM SHAFT

NUT

THROTTLE LEVER

FEELER GAUGE VALVE ROCKER ARM

ROCKER ARMPIVOT

TOP RINGPISTON

PISTON PIN

SECOND RING

Combinationring

FUEL DRAIN BOLTSETBOLT

FLOAT PIN

FLOAT

MAIN NOZZLEFLOAT VALVE

FUEL VALVEPILOT JET

CHOKE LEVER

CHOKE PLATE

MAIN JET

CARBURETOR BODY

THROTTLE STOP SCREW

PILOT SCREW

SEALINGWASHEROIL DRAIN

BOLT

OIL FILLER CAP/DIPSTICK

“UPPER”LEVEL

BALANCER

PUNCH MARKSPUNCH MARKS

CAMSHAFT

TIMING GEARBALANCER DRIVE GEAR

SIDE ELECTRODE

SOLVENT ENGINE OIL

SQUEEZETHOROUGHLY

WIRE BRUSH

Spark plug gap 0.7–0.8mm(0.028–0.031 in)

Standard spark plug BP6ES(NGK),W20EP-U(ND*)BPR6ES(NGK),W20EPR-U(ND*)

AMBIENT TEMPERATURE

20W-40.20W-50

10W-40

10W-30

-20 0 20 40 60 8040℃-30 -20 -10 0 10 20 30

100℉

Engine oil capacity

1.1 (1.16 US qt,0.97 lmp qt)

Standard valveclearance

0.15±0.02mm(0.006±0.001 in)

0.20±0.02mm(0.008±0.001 in)

IN

EX

PISTON DISASSEMBLY/REASSEMBLY CAMSHAFT CARBURETOR DISASSEMBLY/REASSEMBLY CARBURETOR REMOVAL /INSTALLATION

ENGINE OIL

AIR CLEANER

SPARK PLUG

GOVERNOR

IGNITION COIL AIR GAP

VALVE CLEARANCE