Overhaul

Fig. 1 Dual carburetor installation.:

Note installation position of all components prior to removal.
1. Separate the carburetor assembly, Fig. 1, as follows:
a. Remove four vacuum tube attaching screws, then the vacuum tubes from carburetor.
b. Remove upper manifold pipe.
c. Disconnect fuel shut-off solenoid valve and air vent cut-off solenoid valve electrical connectors.
d. Disconnect vacuum hose from carburetor, then remove two lower vacuum tube manifold attaching screws and lower vacuum tube manifold.
e. Disconnect fuel hoses from carburetors, then remove two fuel line attaching screws and fuel line.
f. Remove two idle boost diaphragm attaching screws, then the cotter pin, washer and A/C idle boost diaphragm.
g. Remove throttle opener diaphragm attaching screws, then the throttle opener diaphragm.
h. Remove cotter pin, then disconnect thermowax linkage.
i. Remove two fuel crossover pipe attaching screws, then the fuel crossover pipe.
j. Remove five front bracket attaching screws, then the front bracket.
k. Disconnect choke shaft spring, then remove rear bracket attaching screws and rear bracket.
l. Separate left and right carburetor assemblies.

Fig. 2 Carburetor assembly exploded view.:

2. Remove vacuum chamber, then the vacuum piston and spring, Fig. 2.
3. Inspect piston and needle for wear or damage, replace as required.
4. Remove seal ring and O-ring, then the two screws, plate, jet covers and gaskets from the carburetor to expose the air passages.
5. Remove primary and secondary main air jets and slow air jet.
6. Remove accelerator pump cover, spring and diaphragm from the left carburetor.
7. Inspect diaphragm and spring for cracks or damage, replace as required.
8. Remove power valve cover attaching screws, power valve cover, spring and diaphragm.
9. Inspect diaphragm and spring for damage, replace as required.
10. Remove air vent cut-off solenoid valve from the right carburetor, then the fuel cut-off solenoid valve.
11. Remove float bowl, float arm pin, float and float valve.
12. Remove secondary main jet and needle jet holder, then the primary main jet.
13. Remove power valve jet, needle jet, primary slow jet (located under primary main jet) and power valve nozzle (located under power valve jet).
14. Clean all passages of the carburetor with suitable cleaner, then blow dry with compressed air.
15. Reverse procedure to assemble, noting the following:
a. Install new O-rings, gaskets and filter.
b. Ensure all screws and jets are in the correct position.
10 C c. Ensure choke and throttle shafts move smoothly without binding.

Fig. 3 Carburetor bracket installation.:

d. Tighten front and rear bracket attaching screws as shown in Fig. 3.