How to Clean a Small Engine Carburetor
Universal · 10 min
A clean carburetor fixes most small-engine running problems. This is the single most useful repair skill you can learn. Here's the full process.
What you'll need
- Carb cleaner spray
- Screwdriver set
- Socket set
- Thin wire
- Carb rebuild kit
- Clean rag
Steps
Turn off fuel and remove the carb
Shut the fuel valve, disconnect the fuel line, throttle, and choke linkages, then unbolt the carb from the engine. Take a photo first so you remember how it goes back.
Drain and remove the float bowl
Unscrew the bowl nut at the bottom. This nut is often the main jet too — handle it carefully. Dump out any old fuel.
Remove the jets
Take out the main jet and pilot jet. These have tiny precision holes that clog with varnish — they're the heart of the problem most of the time.
Spray every passage
Blast carb cleaner through every hole, jet, and passage. Run a thin wire through the jet holes to clear stubborn varnish, then spray again to confirm flow.
Replace gaskets
Use the fresh gaskets and bowl o-ring from your rebuild kit. Old hardened gaskets cause leaks and air leaks that make the engine run poorly.
Reassemble and reinstall
Put the jets and bowl back, bolt the carb on, reconnect everything, and turn the fuel back on. Check for leaks before starting.
Start and fine-tune
It should start more easily and idle smoothly. Adjust the mixture screw if needed for a clean, steady idle.
Mechanic's tip
Lay parts out in order as you remove them. A phone photo of the linkages before disassembly saves a lot of head-scratching.