How to Rebuild a Carburetor for a Harley

Close up engine

If your Harley is not running the way it should, it might be time to rebuild the carburetor. S & S is a popular carburetor for a Harley V-twin engine. The fuel to run the Harley runs through the carburetor, mixing with the right amount of air, leaving sediment and particles behind gumming up the inner works of the carburetor. Once the particles are in the carburetor, the bike will not perform as it should. It will run sluggish and possibly not even start. A rebuild kit for the carburetor can be purchased at most motorcycle part supply stores. The process of rebuilding a carburetor is not too difficult.

Difficulty:

Moderately Challenging

Instructions

Things You'll Need

• Screwdriver
• Carburetor rebuild kit
• Carburetor cleaner

1. • 1

     Disconnect the fuel line and drain the carburetor. Remove the carburetor from the intake manifold. Check the plugs that are located in the body of the carburetor for signs of leaking. If signs show that they are leaking, replace the plugs.

   • 2

     Remove the idle mixture screw. Count the turns it takes to remove the screw, make a note of how many turns it took. Check the throttle plate for wear. There should be no light showing when the carburetor is closed. Replace if necessary.

   • 3

     Clean the idle mixture screw and mark it with a marker just to the tapered part. Replace the screw by screwing it completely into the carburetor. Remove the screw and check to see if any of the marker has been rubbed off. If it has, use the new idle mixture screw from the kit and discard the old one.

   • 4

     Remove the enrichment plunger nut and spring from the carburetor. Check the tip of the plunger for wear.

   • 5

     Take the screws out of the bowl of the carburetor. Do not remove the cap.

   • 6

     Remove the float pin screw. Locate and remove the float pin, float and needle. Replace if warn with new parts in the rebuild kit.

   • 7

     Take the seat from the bottom of the carburetor bowl. Install the new seat that is in the rebuild kit.

   • 8

     Check the ejector nozzle for kinks or wear. Install the new nozzle O-ring.

   • 9

     Clean and check the float for holes. Install a new needle. Place the entire unit back into the bowl. Move all the parts to be sure they move easily.

   • 10

     Turn the bowl over and take out the screws that held the cap in place. Take the balls and O-rings out of the casting.

   • 11

     Replace the ball checks, seats, spring and diaphragm with the new ones supplied in the rebuild kit.

   • 12

     Replace the pump shaft and boot. Install the new bowl gasket and secure with the provided screws.

   • 13

     Reinstall the cables before bolting the carburetor back onto the intake manifold.

   • 14

     Position the carburetor with the backing plate and breather assembly and bolt back together.

   • 15

     Replace the idle screw, turning the same number of turns it took to take it out. Start the bike and check the cables. Adjust the idle screw if necessary for the proper idle. Take her for a test ride to ensure all is running smooth.

Tips & Warnings

• Perform each step very carefully.

• Keep the work area and the carburetor clean while rebuilding.

• Clean parts as they are removed and installed or reinstalled in the carburetor.