How to Clean the Carburetor on a 2-Stroke Jet Ski

If you ride an older 2-stroke jet ski, a dirty carburetor is one of the most common reasons it won't start, won't idle, or bogs down. Carbs gum up when fuel sits and dries out — exactly what happens over a winter. This applies to the Kawasaki 550/650/750 SX, the Yamaha 650/700 SuperJet and WaveBlaster, and 2-stroke Sea-Doos. Here is how to clean one.

What you'll need

Before you start, get a carburetor rebuild kit for your model. A good kit includes new gaskets, the diaphragms, and the needle and seat — the soft parts that wear out and cause most problems. You will also want carb cleaner spray and basic hand tools. Find rebuild kits and fuel parts in our Fuel System section.

Step by step

1. Remove the carburetor. Mark and disconnect the fuel lines, throttle and choke cables, and unbolt the carb. Take a photo first so reassembly is easy.

2. Disassemble it. Remove the float bowl (or for diaphragm carbs, the cover plates) and lay the parts out in order.

3. Clean every passage. Spray carb cleaner through all the jets and passages until they are clear. Clogged jets are usually the culprit. Do not force wire through jets — it can change their size.

4. Replace the soft parts. Install the new gaskets, diaphragms, and needle and seat from your rebuild kit. This is the step that actually fixes the problem — old, hardened diaphragms won't seal.

5. Reassemble and reinstall. Put it back together, bolt it on, reconnect the lines and cables.

One caution

If your carb has an adjustable pop-off pressure or low/high-speed screws, only adjust them if you know your baseline settings — get these wrong and the ski can run lean and damage the engine. When in doubt, follow your service manual.

Shop carb kits, fuel lines, and the rest in Fuel System, or browse parts for your machine in 90s Kawasaki and Yamaha SuperJet.