Fuel spilling when brimmed - 1990 diesel

[shampooefficient]

Evening all.

Woman thought she'd be nice and brim her mum's camper earlier, before taking her out. Unfortunately when filled it spat a bit out, apparently out of the fuel neck and also from the tank area.

MrsSE must have done some grovelling before leaving the pumps.

It's had a new fuel tank before we bought it (after doing the same before). I'm guessing there's a pipe off somewhere... Or is there any sort of valve or something we should be looking at?

My Google fu is failing this evening so if there's a guide or something I've failed to see, please feel free to insult me and link to it

TIA.

[Stesaw]

There's the breather system on the top of the tank that consists of a crossover pipe and two other pipes that attach to the tank directly( one either side) and then they go to the plastic breather boxes in the wheel arches. The crossover pipe sits in rubber grommets and they can pop off when fitting the tank and if not checked afterwards the tank will be open to the elements.

You can check the crossover pipe from the wheel arches.. just make sure its sitting in the grommets.
The filler seal could be duff but if you've had a new tank it should all be OK... just don't brim the tank. Its about 60L if I recall.

Its worth noting that the breather boxes in the arches have valves in them. Worth checking them to make sure they aren't stuck.

[shampooefficient]

Thank you SO much for the detailed help. Never fiddled with anything as quirky as a rear engined VW before so learning as I go and it's very handy that this forum exists to hold my hand.

I'll have a good look at it this week. Thank you!

[Stesaw]

Those are the pipes you can access from both sides of the wheel arches. Make sure they are in the tank and the rubber seals are OK

[mioba]

Breather pipes under the arches. A service item.