Partial vacuum in Discovery fuel tank

Hi Chaps,
I have a problem with my 300 Tdi, when the fuel filler is opened there is a sucking sound. I have put this down to the tank somehow pulling a partial vacuum.

I gather there's a breather pipe on the tank which I guess could be partly blocked, but despite looking in both the workshop manual and Mr Haynes book of lies, I can't find any pointers as to where the breather either comes out of the tank or where it goes to.

I cleaned the sedimenter last weekend and whilst I was under the vehicle I did have a look round but couldn't identify the breather.

I'm probably missing something obvious but any assistance will be greatly appreciated.

I've done a search on the forum but came up with a blank

regards Brian V

I know the old Range Rover's had a tank breather run up the rear quarter panel and they had a tendancy to get blocked once in a while. I'll have a look in my Haynes see if I can find out for sure about the Disco's as that info could be wrong!

I believe that the 300ti breather runs either inside the fuel filler or inline with it. my mate had this problem as he had a oem filler cap. I think all he did was make sure its clean. Will check the manual for you- thats where i found it

Fuel sysyem
A 89 litre fuel tank is mounted at the rear of the vehicle beneath the load space floor. The tank is vented by a 2 way valve in the filler cap..

Well there you have it....