Alfa 155 Fuel Leak

I've got a fuel leak on my 155. I checked underneath, and could see it was coming from the top of the fuel tank. So i went into the boot, removed the plastic cover and can see fuel(where the connectors, and pipes come out - sorry for the non-technical wording).
I can see fuel sitting in there, and know the leak is there (somewhere). The thing is, the pipes look fine and not perished, and i let the car tick over for around 20 minutes and didn't see a drop. There is still residue on the tank from the past few weeks, but it must be quite a slow one, and i can smell it every time i go for a drive.
Anyone any ideas where to look, or how to find the leak in that area?

The plastic fuel pipes are bonded to white plastic connectors that fit into holes in the top of the fuel pump. The connectors have an O-ring which fits into the joint to make the seal with the fuel pump but are only otherwise held in place by the metal collar you can see, held tight by that M6 nut.

The O-rings could be perished and causing a weep but what probably happened is that the metal collar has been fretting against the plastic connectors and worn through one of them.

You need to remove the collar and have a look. If the connectors don't appear to have been worn through by the collar vibrating against them, the O-rings could be the culprit.

Pull out the connectors to have a look at the condition of the O-rings.. but be careful.. the fuel lines are pressurised and when you remove the connector, about 5 gallons of fuel will spurt out under pressure. Best to make sure you're not smoking at the time...

Good news is that a new fuel pipe and connector (1-piece part) is fairly easy to fit.. It runs down to the fuel filter under the car). The bad news is that this part is like Dodo droppings... You may have to get a new one fabricated at your local fuel pipe fabricators.

Ralf S.

had the same prob with my Q4, replaced the O-rings, still leak'd ! had to order new pipe through main dealer, had a two week wait but got it ok !

Thanks for the advice.
Finally got around to having a look today. I removed the metal collar, and the pipe itself looks fine, unfortunately so do the rubber O rings. I'm going to change the O rings first (or try a sealant - any ideas?).
One problem i do have is that the bolt for the metal collar snapped. I now have part of the bolt inside, and can't remove it. It won't loosen with Mo-Grips, and i managed to saw a slit in the top to put a scewdriver in - still won't undo.
Any ideas? I tried to take of the whole piece by removing the large white collar from the fuel tank, but there seemed to be a minefield underneath, and wouldn't pull out.

That white collar ring holds the fuel pump in place.

It's okay to remove it but you have to jiggle it about to get the bits of metal etc. out of the hole in the top of the fuel tank.

I can't remember if the stud is part of the fuel pump.. if it is, then it'll be bonded into the plastic top of the pump and you won't be able to unscrew it.


Ralf S.

Hope things work out for you, Skiibzee