GT6 Fuel Filler cap

[Alex Lowe]

Hi All 

Having a strange problem, took the MK3 GT6 out for one of its first drives the other week and noticed a smell of fuel after going around a sharp corner and noted fuel had leaked back out of the filler cap and down the side of the car. Is there meant to be an over flow pipe if so would any one have a photo of where is should be located and or any ideas on how to solve the problem?

[Colin Lindsay]

Mk3 fuel filler exited the floor just behind the wheel arch on the filler cap side; if you have one you'll see about an inch of hose hanging through a hole in the floor. 

[NonMember]

As Colin says, the filler flap assembly has a small drain hole in the bottom which should have a hose out through the boot floor. However, that's probably not enough to stop splash on hard cornering if the rubber seal on the filler is no good. The filler cap should close tight enough to hold the fuel in the tank / neck. It's not intended to be a breathable cap on the MK3 - there should be a separate breather pipe from the tank or filler hose (I can't remember which off-hand - the same cap is used on 2000 estates and Stags but I think the breather arrangement is different).

[Stewart Vacher]

Thought his diagram might help

Stewart

[Nigel Clark]

Check the rubber seal on the cap carefully. As said in the above posts, the tank vents through a separate pipe running down from the filler neck. I've found the replacement rubbers for the cap don't always stay in place and seal properly, so check that the smell isn't from fuel leaking past the cap when the tank is fairly full. Have a good look at the cap seal and mechanism, does the spring on the cap operate properly and does the locking lever more freely without disturbing the sealing rubber.

Nigel

[Alex Lowe]

Will go and check all these but from memory it doesnt have the lower pipe in the diagram yet has the one which runs under the fuel tank whats the difference between the two. And should there be a hole in the tub for the one which i seem to be missing?

[Qu1ckn1ck]

I had this problem and found the cap does not seal properly so replaced the seal with a new one.  Still had petrol slopping out when tank was full so I now have two seals together, a bodge but it has done the trick.

I just have to be careful when filling that I do not lose the second seal.

[Colin Lindsay]

1 hour ago, Alex Lowe said:

Will go and check all these but from memory it doesnt have the lower pipe in the diagram yet has the one which runs under the fuel tank whats the difference between the two. And should there be a hole in the tub for the one which i seem to be missing?

That's a stranger setup; it appears to show two different oveflow / drains - the shorter one to the right was the setup I had in my 1973 Mk3; is the other side venting - the dotted line under the tank - for LHD models?

[Alex Lowe]

Problem all sorted now overflow pipe is not fitted and temporary gasket fitted as i seemed to be lacking one previously they joys of buy many other peoples project.