General Repairs
- Disconnect battery ground cable before attempting any repairs of the carburetor. When carburetor is disassembled, wash all part, except the automatic choke cover, in gasoline. Sticky deposits may be removed with acetone.
- Check that vacuum piston for the automatic choke moves freely. Blow out jets, valves, and drillings with compressed air.NOTE: Never attempt to clean jets with pins or wire.
When replacing jets, note jet flow directions: Jets marked "O" have flow direction opposite jets marked "X" (see illustration).
- Replace all gaskets and sealing washers. Check float needle valve for leakage. It should not be possible to blow air through the valve when needle is pressed lightly onto its seat. Check that needle moves freely and note thickness of washer under valve.
- Place float in hot water and check for leaks. If bubbles appear, replace float.
- When checking the electromagnetic pilot jet cutoff valve, the pilot jet can be screwed off the cutoff valve, as illustrated, and blown out. Check valve by switching current off and on and listening for clicking noise which indicates valve is moving in and out.
- Carburetor bodies with worn choke valve and throttle valve bearings should be replaced. Oil all bearing points lightly. Lubricate all bearings and ball joints of linkage with a molybdenum disulfide-base paste.
- When replacing large sealing plug on side of carburetor body, lightly coat sealing face of plug with D3 compound. Remove all burrs from the drilling. Install plug with groove at the bottom. Expand the plug by peening.
- When reinstalling accelerator cable, secure it after placing throttle in full open position and insuring there is a gap of approximately 0.04" (1 mm) between throttle valve lever and its stop on carburetor body (see illustration: measurement "a").
- When installing a new throttle valve positioner, the pull rod must be adjusted. The special lever must not touch the carburetor body or throttle valve lever when throttle valve is closed (see illustration).