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How To Clean A Carburetor | MC GARAGE

Fast becoming a lost art in motorcycle mechanics is the rider’s ability to service the carb.

September 12, 2015

©Motorcyclist

The fuel systems on older carbureted bikes require regular maintenance. This includes tending to the petcock, fuel filters, fuel lines, and the carburetor(s). This month's How To walks you though the process of cleaning a carburetor.

1 // Drain the carburetor and remove it from the bike. This might require displacing the airbox. Take note of hose and cable routing. Look for dry, stiff, or cracked flanges on the intake and the airbox, and replace anything that looks suspicious.©Motorcyclist

2 // Clean any grime from the exterior of the carburetor with a soft brush and an aerosol carb cleaner then remove the screws that secure the float bowl to the bottom of the carb. If the float bowl is stuck in place, give it a firm tap with the handle of your screwdriver.©Motorcyclist

3 // The float bowl may be full of gunk and scale. (This one, ironically, was spotless.) Clean out the bowl with a brush or by scraping the deposits with a pick or small screwdriver. Really thick or stubborn deposits could require submersion in a stronger chemical cleaner, often available at auto parts stores.©Motorcyclist

4 // Remove the float by pulling the hinge pin. Inspect the float needle and shake the float—any liquid inside is evidence of a leak and necessitates replacement. Inspect the slide piston for wear, and on constant-velocity carbs check the rubber diaphragm for tears or damage, and replace if necessary.©Motorcyclist

5 // Remove the jets. The main jet is in the center and the pilot jet (sometimes a non-removable fixed unit) is the smaller one next to it. Seat the air screw—noting the number of turns to closed—and then remove it.©Motorcyclist

7 // The bores of the jets and all emulsion holes must be clear. Remove any stubborn obstructions with an appropriate item. The kinky bristle from a brass brush is ideal for this purpose. Do not use drill bits to clean jets.©Motorcyclist

8 // Give all the parts a final rinse with carb cleaner and reassemble the carburetor. Make sure to reset the air screw to its original position. Reinstall, add gas, and go for a ride!©Motorcyclist

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