Bizarre rapid fuel leak problem
 

I took my series 3 out today, filled both tanks, then drove around 30 miles with a stop in the middle. Everything was perfect until 500 yards from home when another car flashed me down to tell me petrol was pouring out all over the road behind me - which it was. The petrol was pouring out like a tap, not merely dripping!

Upon getting home I crawled under the car and it appears to me that the petrol was pouring from a small down facing pipe which looks to me like an overflow or something.

The right tank now seems to be almost empty, but the left tank (which I thought I'd been using throughout my 30 mile journey) seems to be practically overflowing.

The mechanism to switch tanks appears to be working because when I put my ear to the right tank (the ones that’s nearly empty) I can hear the fuel switching around, then if I throw the switch and listen again it's stopped.

Is there ANY reason why my car would have purged it's fuel like this? It seems to have been fine all day, then suddenly

Any ideas? :icon_confused:

A stab in the dark, or not even that "precise". I can not identify the pipe you describe. Because to my understanding, this a completely closed system.


But, your description suggests a failure of the selection valve. Using from one tank, but returning x's to the other.


Carl

I think you're onto somthing..

With the selection switch in the position where I can hear petrol slpashing/swirling around in the right tank, the level on the left tank which WAS overflowing seems to have dropped a little.

it's one of the return valves gone haywire. They are located in each rear wheel opening, behind a bracket / cover. You need to remove the rear wheel(s) to see the brackets. Time to replace both of them.

Almost certain a faulty return valve, yes. This might be of interest:

https://www.jaguarforums.com/forum/x...6-12-a-196397/

A little more in depth description:

Fuel Tank Switchover Checklist, Series III XJ6

Cheers
DD