Tank vent valve

Hi All,

Can anyone tell me if the breather valve on top of the fuel tank is one way or should I be able to blow both ways through it. There is a arrow that points towards the charcoal cannister. 

It rattles but I can blow through it both ways ?

Hi

the arrow is direction of flow which should be just that  so you shouldnt be able to blow both ways 

A tank vent lets pressure out but stops anything  going back in 

So i would say yours is duff 

Ah, ok. Thanks for that. Now could somebody point me in the right direction for purchasing one, cheers.