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Why is fuel coming out vent tube on Mikuni model HSR42 carburetor?

1. Float valve stuck open

- Most common cause when fuel comes flooding out a carburetor's vent tube

- Could just be dirty or may even have debris holding it open

- Could also be float tang is bent

2. Float height set too high

- This causes insufficient pressure holding closed the float needle or float valve seat

3. Carburetor is cracked

- Typically from someone over tightening carburetor and breaking casting near float bowl drain vent tube fitting