Fuel Tank Breather Problem

[carlh.1 8]

I've just removed the fuel tank off the car because I have trouble filling it with fuel, it always seems to gulf back out the filler cap.

On the tank I have a 20mm pipe which must be the breather.

 

I'm just wondering what the small 6mm pipe is for because I cans blow down it.

 

Cheers Carl

[mhyphenl 10 1 Cars]

the 20mm pipe is the breather and when you put the cap on both the filler pipe and breather are shut air tight. the 6mm pipe is the permanent vent for the fuel tank to stop a vacum forming! It's vented to the air normally with a one way valve hidden above the filler pipe!

[dobboy 231 2 Cars]

Mine has a white plastic barrel type thing fitted on the end of it, and mounted behind rear valance somewhere.

[carlh.1 8]

That's why I can't blow down the smaller pipe then because of the one way valve, I'll clean the larger breather out because the cars shocking to fuel up. I loose the will to live before the tanks full having to fill it so slowly.

Cheers for the help!