Petcock Query

[zeebob]

As I was draining the gas from my tank yesterday I noticed that the fuel would run thru the pepcock at the same speed despite the setting, that is, RES, ON, PRI.

Why is that?

I thought that it would only run on prime, as the others require vacuum to operate.
I would add that I haven't had any issues with the petcock such as fuel in the airbox or oil etc.

TIA for any responses/thoughts
Z

[tom203]

As I was draining the gas from my tank yesterday I noticed that the fuel would run thru the pepcock at the same speed despite the setting, that is, RES, ON, PRI.

Why is that?

I thought that it would only run on prime, as the others require vacuum to operate.
I would add that I haven't had any issues with the petcock such as fuel in the airbox or oil etc.

TIA for any responses/thoughts
Z

Why??? your petcock has failed, but apparently your carb floats /seats are doing their job and holding back the tide of gas. Don't rely on this-just get a new petcock.

[Guest]

Your petcock should only allow gas to flow in "On" or "Res" when there is vacuum applied to the petcock, which is when the engine runs.