Unclog A Keihin Carb On A Harley

To access the carburetor, you will need to remove the air cleaner first.

Clogged carburetors are a typical problem faced by Harley-Davidson motorcycles during extended periods of inactivity. This is especially true for models equipped with Keihin carburetors, which are affected by a sludge-like byproduct of old gasoline. This sticky, greenish sludge coats the carburetor’s fuel jets and float bowl, preventing air and fuel from being fed to the motor. The end result is a motorcycle that refuses to start and runs poorly when it is does start. Removing these clogs requires removal and disassembly of the carburetor, but don’t worry, the task is easier than it appears.


1. Use a screwdriver to unscrew the bolts from air cleaner’s outer cover. Pull the outer cover away from the air cleaner assembly. Remove the air filter element. Unscrew the bolts that secure the air cleaner assembly‘s inner cover to the carburetor with a screwdriver and pull the inner cover away from the motorcycle.

2. Turn the fuel valve to the “off” position. Disconnect the fuel line from the carburetor and allow any remaining fuel to drain into a container. Unscrew all three bolts that secure the carburetor’s float bowl to the carburetor using a screwdriver. Place a container beneath the carburetor and remove the float bowl, empty any fuel remaining in the float bowl and carburetor to drain. Remove the carburetor from the motorcycle using a wrench to loosen the lock nuts that secure the carburetor to the intake manifold.

3. Place the carburetor on a clear workspace. Using a small screwdriver, unscrew the fuel jets and remove them from the carburetor’s body. Clean the jets using a thin length of wire, pushing the wire through the jet’s passage to remove any buildup. Clear any remaining debris from the jet’s passage using compressed air. Repeat on any remaining jets.

4. Spray the interior of the carburetor with an aerosol carburetor cleaning agent. Apply a liberal amount of cleaner to the carburetor’s fuel and air passages, jet holes and float bowl. Clear any remaining debris from the carburetor and its passages using compressed air.

5. Reassemble the carburetor, screwing the jets into the carburetor body with a small screwdriver. Reattach the float bowl to the bottom of the carburetor and tighten all three float bowl bolts with a screwdriver.

6. Mount the carburetor onto the motor’s intake manifold, sliding the studs on the carburetor’s flange through the holes on the intake manifold. Place a lock nut on the protruding end of the carburetor’s studs and tighten with a wrench to secure the carburetor. Reconnect the fuel line to the carburetor.

7. Reassemble the air cleaner assembly on the carburetor. Place the inner cover over the carburetor and tighten the mounting bolts with a screwdriver. Place the air filter element onto the inner cover and mount the outer cover over it. Insert and tighten the outer cover’s screws with a screwdriver.