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Small Engine Repairs and Troubleshooting

Experience is the name everyone gives to their mistakes. -- Oscar Wilde

You can complain because roses have thorns, or you can rejoice because thorns have roses. Ziggy

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Mikuni Carb 15003 - Carb bowl and bowl nut in position

Kawasaki FC540V-CS00 with Mikuni carb 15003-2131 assembly and cleaning

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Photo - Mikuni Carb 15003 - Carb bowl and bowl nut in position^ Photo 1. Carb bowl in position and bowl nut loosely in place

This page shows the disassembly of a Mikuni carb 15003-2131 on a Kawasaki FC540V-CS00 engine (John Deere label).

Remove the carb bowl by unscrewing the bowl nut at the bottom (Photo 1 ). The bowl may be stuck on the gasket (O-ring) so give it a twist and a pull.

Photo 2 shows the carb with the bowl removed. Easily seen are the float and the bowl gasket.

Photo - Mikuni Carb 15003 - Close-up image of bowl gasket in place^ Photo 2. Bowl gasket seated in carb body
Photo - Mikuni Carb 15003 - Carb inverted showing float parallel to carb body^ Photo 3. Carb inverted showing float parallel to carb body

For the float to operate properly it should sit parallel to to carb body when the carb is inverted (Photo 3). If it does not sit properly there may be dirt / debris in the seat, the needle may be damaged, or the float may be damaged.

The float is held in place by a hinge rod. One end of the rod has a flat (Photo 4). Remove the hinge rod by grasping it on the flat with needle-nose pliers and rotating it back and forth while sliding it out. The float can now be lifted out. The float needle will probably come out with the float so don't lose the needle.

Photo - Mikuni Carb 15003 - Carb inverted with float in place^ Photo 4. Carb inverted with float in place
Photo - Mikuni Carb 15003 - Main jet screws into main jet holder^ Photo 5. Main jet screws into main jet holder

The main jet shown in Photo 5 can be unscrewed and removed for cleaning. Next, the main jet holder is unscrewed and removed (Photo 6).

Photo - Mikuni Carb 15003 - Main jet holder assembled to carb^ Photo 6. Main jet holder assembled to carb
Photo - Mikuni Carb 15003 - Main nozzle slides into place^ Photo 7. Main nozzle slides into place

The main nozzle is the piece that sticks up into the throat of the carb. It can be removed by pressing lightly on it from the venturi area. It does not have threads. It just slides out. (Photo 7).

The air screw (low idle mixture adjustment) unscrews for disassembly. Its basic setting is 1-1/2 turns from seated. (Photo 8).

Photo - Mikuni Carb 15003 - Pilot air screw assembled to carb^ Photo 8. Pilot air screw assembled to carb
Photo - Mikuni Carb 15003 - Pilot jet retainer plate assembled to carb^ Photo 9. Pilot jet retainer plate assembled to carb

The pilot jet (air bleed) is held in place with a screw and retaining plate (Photo 9). Once the retainer is removed, the jet can be pulled out with needle-nose pliers (Photo 10). It is not threaded.

Photo - Mikuni Carb 15003 - Pilot jet assembled to carb^ Photo 10. Pilot jet assembled to carb

Previous: Disassembling the carb from the engine

Baseball is ninety percent mental. The other half is physical. -- Yogi Berra