3 4 6 7 8 10 119
Fuel filter
Solvent
Check for cracks Check for cracks Clean themain jet passage Check metering lever distance
Metering lever Pump body0.3 mm.
1.18-1.50 mm.
Check for wearof valve andvalve seat
valve
valve seat
Clean or replace Check for damage Check for damage Adjust idle speed3,100 ± 200 rpm.
Throttle stop screw
Check for crack
Replace OK
Carburettor Check Sheet GX25 - GX35
Caution Point
• Fuel Flow ChartFUEL
COMPRESSION IGNITION
COMbUSTION ELEMENTS
If the engine will not start, before inspecting the fuel system, check that the engine has sufficient compression and a strong spark.
5 8 9Priority check Points :
1
Swivel
Free play 0.5-2.5 mm.
Throttle cable end
Return
AIR
In
10
7
4
8
6
5
9
3
2
1 2 5Fuel filter
Primer pump
Metering lever
Operate primer pump
Engine running
Do not adjust idle needle pin during carburetor mainte-nance.
The pump and metering diaphragms are made of rubber. Rubber deterio-rates over time, so check and replace these parts if necessary.
Do not apply high air pres-sure to plastic and rubber parts.
Check for cracks, holes, tears and general perishing of the rubber parts. Clean with a soft brush.
If the engine will be stored, or not used for more than 1 month, drain the fuel to prevent hard starting.
1. Drain fuel from tank 2. Drain fuel from carburetor
3. Drain fuel from fuel tank again
4. Keep engine in shady ventilated storage
Do not use old fuelFuel deteriorates quicklyOld fuel makes engines very difficult to startAlways use fresh fuel
Inspectionpoint
Hard to prime with primer pump
Engine does not start
Idle speed is not stable
High speed is not stable
Engine does not accelerate
Overflow
AIR AIR
Combination valve
Main jetInlet needle
valveFuel inlet
filterPump
diaphragmThrottle
stop screwShroud
Metering diaphragm
Prin
ted
In B
elgi
um -
Pub
lishe
d by
: Ho
nd
a E
uro
pe
NV
Eur
opea
n E
ngin
e C
ente
r -
Spe
cific
atio
ns c
an b
e ch
ange
d w
ithou
t no
tice
- E
ditio
n: 7
744
Nov
. 201
2
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