Auxiliary Gas Fuel Tank question

[Guest]

Hello, I'm working on tuning my carb setup, and I'm going to borrow my buddy's hanging auxiliary fuel tank so I can reach the screws in the carb (and eliminate the petcock as a possible problem). Since I won't be using the petcock, and therefore not the vacuum valve for the petcock, I assume this will be similar to running the petcock in the Prime position. Is it bad to do this for any length of time? I understood you only use Prime to get your system full of fuel, then you switch over to run. Anything I should do while using the hanging tank?

[hannibal]

I wouldn't leave it overnight, but I don't think 15-30 minutes would cause any problems. From a carb's perspective, it's just like idling with the tank on, vacuum line connected, and petcock set to run.

Don't forget to plug the vacuum line from the carbs.

[JTGS850GL]

2nd what Jardan said. There is no difference between running it in the PRIME position and running it in the ON position. As long as the engine is running the petcock is open. Never leave it in the Prime position for more than a minute when the engine is off. I put an inline valve on my aux tank and turn it off when the engine is not running.

[Ian Donahue]

Hey thanks for clearing that up and double thanks for the tip on plugging the vacuum, that would have stumped me I'm sure!