FUEL SYSTEM
CS-2510TES
250Ts, 250TCs
39
4-12 Inspecting diaphragm and others
1. Inspect metering diaphragm (A) for hardening,
distortion, or pin hole. Replace as required.
2. Remove pump cover (B), pump diaphragm (C)
and pump gasket (D).
3. Inspect pump diaphragm (C) and replace if
hardened or curled at valve tabs.
4. Make sure pulse chamber is clear of debris. If
not, clean it.
5. Inspect metering gasket (E) and pump gasket (D)
and replace if defective.
6. Inspect inlet screen (F). If blocked, remove and
clean it, or replace.
7. Clean pulse passage (G) with compressed air.
8. Clean fuel passages in carburetor body with
compressed air.
NOTE: Before cleaning metering side with com-
pressed air, turn “H” needle clockwise until lightly
seated and remove inlet needle valve. Otherwise,
main nozzle check valve and inlet needle valve
spring may be damaged by the compressed air.
9. Reassemble removed parts with particular at-
tention to each aspect.
4-13 Replacing welch plug
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
tool 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.
A
B
C
A
B
C
D
E
F
G