no off position on petcock

[Guest]

got myself a nice 1981 gs450 with a petcock with three positions: on,reserve,and a "pri" (for prime i believe). that leaves no "off" position. do i have to replace it so i can turn the gas off from the tank? thanks

[BassCliff]

Hi,

Have a look at this...

Where Do These Hoses Go?


Thank you for your indulgence,

BassCliff

[whenpigsfly514]

My bike has the same petcock, it doesnt have the fuel send unit either. Never had one.

I have the drain tube, vent tube and supply tube.

Still doesnt answer if how I turn the fuel off?

[terrylee]

works off vacuum, if "on" or "reserve" will only work when bike is running. If it works without it running, petcock is bad. Prime position will allow fuel to flow without bike running. Good for when bike has not been started in a long while, can put on prime for minute or two to "prime" carbs for easier start. terrylee

[hjfisk]

it turns off automatically when the bike is not running, it is vacuum operated no off position. when you remove the fuel hoses make sure it is in the run or reserve position, if it is in prime position fuel will flow. If it flows fuel in the on or reserve position you need a new petcock. or if fuel is in the vacuum line

[nikosg]

^^ yup.

Unless the bike is running, there is nothing "sucking" the fuel out. therefore you can just disconnect it when its in the ON position and nothing will happen.

[Steve]

^^ yup.

Unless the bike is running, there is nothing "sucking" the fuel out. ...

There is nothing that "sucks the fuel out".

The vacuum merely pulls on the diaphragm that opens the valve, letting the fuel flow on its own, due to gravity.

.

[chadams66]

oh..that's the story

thanks for the information, i was wondering what the "deal" was. i haven't tried pulling the gas line off yet, so i can't say if it's working correctly. guess i'll find out when i get to rebuilding the carbs. thanks again.