Inspecting Diaphragm; Replacing Welch Plug - Echo CS-310 Service Manual

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4-13 Inspecting diaphragm

4-14 Replacing Welch plug

B
A
FUEL SYSTEM
1. Inspect metering diaphragm (A) for hardening,
distortion, or pin hole. Replace as required.
2. Remove pump cover (F), pump diaphragm (D)
and pump gasket (E).
A
3. Inspect pump diaphragm (D) and replace if
B
hardened or curled at valve tabs.
4. Inspect metering gasket (B) and pump gasket (E)
and replace if defective.
5. Inspect inlet screen (C) if blocked, remove and
clean it, or replace.
C
6. Clean fuel passages in carburetor body with
D
compressed air.
E
NOTE: Before cleaning metering side with com-
pressed air, turn "H" needle clockwise until lightly
F
seated and remove inlet needle valve. Otherwise,
main nozzle check valve and inlet needle valve
spring may be damaged by the compressed air.
If engine does not run smoothly even after read-
justing carburetor and inspecting carburetor parts,
inspect low speed ports on carburetor as follows:
1. Remove metering lever and related parts to pro-
tect them from damage.
2. To remove Welch plug (A), punch the remover
tool (B) through Welch plug at low angle and pry it
out.
NOTE: Remover tool (B) is included in Welch plug
C
tool (Part number: 500-500).
3. Clean low speed ports with compressed air.
4. Place a new Welch plug over the opening and
gently tap it until fl ush using welch plug installer (C).
5. Install all removed parts to carburetor body.
CS-310