XC70 D5 fuel tank leak on rear passenger side when tank full

[palwing]

Hi. My 2005 XC70 D5 has just developed a fuel leak. Parked it on our flat level drive and had diesel dripping from the tank just under the rear passenger door. The car has done about 150 miles on a full tank. Had a look underneath, best I could. It appears it’s coming from above the tank, but can’t be sure. The rear underneath of the car on that side is wet with diesel, but NOT on the tyre or inside of the wheel/brakes. I moved the car onto out gravel so it might soak up any more drips. Since moving the car, the drip seems to have stopped and the fuel gauge is reading just above 1/2 a tank remaining with the readout saying the range left is 440 miles. I am thinking that it only leaks when the tank is above a certain level or full? Could this be the fuel pump problem or seal requiring the removal of the rear seats that I have read about? Does that cause a leak on the passenger side? I have my friendly local mechanic going to have a look at it on Tuesday 24th March. Anyone else come across this problem? Any I nfo appreciated. Thanks.

[Bashy]

I have heard there filler pipe can be an issue, perhaps its that and its taking a path across the tank, im just guessing.

Just be careful, is the leak anywhere near the exhaust?

[palwing]

Thanks Bashy. Will check it out, especially the exhaust bit. Took it for a run yesterday but no leak to see. Seems to be leaking when around 2/3 full or more.

[green van man]

From memory the filler pipe enters the tank about 2/3 up from the bottom, there is then a breather that allows the fuel to fill to the top of the tank and some sits in the filler pipe.

I would be checking all pipes and clips first. While it is possible the tank is damaged you would be really unlucky for that to of happened. It's a plastic tanks so corrosion can be ruled out.

It was on the cooling system I know but I did once have a water leak caused by a volvo hose clip rusting through and not clamping the flexable pipe to the stub.

Paul.

[Tatsfield]

I'd put money on it being the breather hose.

[palwing]

Thanks for your replies. Unfortunately I am back in hospital, so can't check your suggestions out or take the car to my friendly mechanic tommorrow as planned. Have been keeping the level at 50% for now with no sign of a leak. I would rather it's fixed though. Will do more if I ever escape.

[broneif]

I agree with Tatsfield, I could smell diesel and notice stain on passenger side tank next to prop shaft on my XC70 .Whilst underneath, noticed a pipe with white breathing trap hanging down below level of top of tank. Have re-attached the pipe and breather head above top of tank, problem cured.

[Simmy]

Originally Posted by palwing

Hi. My 2005 XC70 D5 has just developed a fuel leak. Parked it on our flat level drive and had diesel dripping from the tank just under the rear passenger door. The car has done about 150 miles on a full tank. Had a look underneath, best I could. It appears it’s coming from above the tank, but can’t be sure. The rear underneath of the car on that side is wet with diesel, but NOT on the tyre or inside of the wheel/brakes. I moved the car onto out gravel so it might soak up any more drips. Since moving the car, the drip seems to have stopped and the fuel gauge is reading just above 1/2 a tank remaining with the readout saying the range left is 440 miles. I am thinking that it only leaks when the tank is above a certain level or full? Could this be the fuel pump problem or seal requiring the removal of the rear seats that I have read about? Does that cause a leak on the passenger side? I have my friendly local mechanic going to have a look at it on Tuesday 24th March. Anyone else come across this problem? Any I nfo appreciated. Thanks.

i had this exact same problem only leaked when filled more than half a tank it was fixed by replacing the seal on the top of the tank which i sourced from another member on here.there was some slight damage to the ring which screws into the tank caused by someone using a screwdriver or similar instead of the correct tool. its easy access by the removal of a panel under the rear seat. no need to remove the seat.