I know the 80-83 vacuum petcock markings & function has been discussed before.
Q. Why do the carbs flood, gas leaks in the PRIme position... some have said "because the fuel is constantly flowing, vacuum or not. " I don't buy this, before I put my bike in two year storage the carbs never flooded/leaked no matter what position the valve was in, running or not !
To reiterate it has 3 positions: On, Reserve & Prime.
In the On and Reserve positions, the flow is stopped until the engine is running & (hose going to cylinder heads) creates vacuum . The vacuum opens a diaphragm & allows the fuel to flow.
Now, if I understand carbs correctly, fuel continues to flow into the bowl raising the float until it pushes a little needle/seat & stops; thus keeping the fuel in the carb bowl at a constant level (necessary for proper venturi & fuel distribution)
So.... I am wondering in the PRIme position, why are the carbs flooding all of a sudden ? If it were a bad needle/seat (or float) I would think the carbs would flood once the bike started running (yeah great a stream of napalm gas trailing from the bike).... in fact this is what I though was going on until I turned the valve from "PRIme to ON".... the thing ran fine, didn't flood/leak & didn't run out of gas when I cruised it !
I know it's a moot point since I am going to change to the earlier non vacuum petcock anyway (with simple, true On Off and Reserve).... but has me a bit confounded !
Q. Why do the carbs flood, gas leaks in the PRIme position... some have said "because the fuel is constantly flowing, vacuum or not. " I don't buy this, before I put my bike in two year storage the carbs never flooded/leaked no matter what position the valve was in, running or not !
To reiterate it has 3 positions: On, Reserve & Prime.
In the On and Reserve positions, the flow is stopped until the engine is running & (hose going to cylinder heads) creates vacuum . The vacuum opens a diaphragm & allows the fuel to flow.
Now, if I understand carbs correctly, fuel continues to flow into the bowl raising the float until it pushes a little needle/seat & stops; thus keeping the fuel in the carb bowl at a constant level (necessary for proper venturi & fuel distribution)
So.... I am wondering in the PRIme position, why are the carbs flooding all of a sudden ? If it were a bad needle/seat (or float) I would think the carbs would flood once the bike started running (yeah great a stream of napalm gas trailing from the bike).... in fact this is what I though was going on until I turned the valve from "PRIme to ON".... the thing ran fine, didn't flood/leak & didn't run out of gas when I cruised it !
I know it's a moot point since I am going to change to the earlier non vacuum petcock anyway (with simple, true On Off and Reserve).... but has me a bit confounded !
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