Maintenance Information; Troubleshooting - Sym RS-50 Service Manual

10. FUEL SYSTEM

Maintenance Information

Precautions in Operations
Warning
Gasoline is a highly flammable material and may explosive under circumstance. Thus, always work
in a well-ventilated place and strictly prohibit flame when working with gasoline.
Care must be taken when dealing with gasoline, and always work in a well-ventilated place and
strictly prohibit flame.
When disassembling fuel system parts, pay attention to O-ring position, replace with new one as
re-assembly
It has to conduct air bleeding operation as removed the oil tube.
Idle speed adjustment.
Specification
Item
Venturi diameter
Fuel level
Air screw opener
Idle speed
Throttle handle free play

Troubleshooting

Engine can not be started
1. No fuel in fuel tank
2. Fuel can not reach to carburetor
3. Too much fuel in cylinder
4. Clogged air cleaner
Stall after started
1. Incorrect idle speed adjustment
2. No spark on the spark plug
3. Low compression pressure
4. Rich mixture
5. Lean mixture
6. Clogged air cleaner
7. Inlet pipe leaking
8. Polluted fuel
10-2
This chapter Contents
Lean Mixture
1. Clogged carburetor jet
2. Clogged hose from carburetor to canister
3. Bend, squeezed or clogged fuel lines
4. Clogged fuel filter
5. Malfunction of float valve
6. Low fuel level in float chamber
7. Clogged vent pipe
8. Malfunction of fuel pump
Rich Mixture
1. Malfunction of float valve
2. Low fuel level in float chamber
3. Clogged carburetor air injector
RS-21 50
15 mm
8.8±1.0mm
1 3/8
2000±100 rpm
2~6 mm