Facelift Strange Leak

That’s a good theory. I have never considered that. My top is still original. I wonder if the paper towels I will shove in there will reveal that.

I am starting to get a little water in by the drivers side handle. Maybe it’s time….

I will do my best to keep the car out of water and see if more oil gets in.

Between vacations, and kids back from school, it’s been challenging to find time to work on the Jag, but I ended up dumping in a fuel dye and my trunk has lit up like a Christmas Tree with the black light. It most certainly is the fuel tank.

I have to take this back to the shop that I had seal coat the tank last year. Will keep everyone posted.

Talked to the shop yesterday. WIthout getting a lot of detail, the tank was not leaking, but there was some kind of failure at the purge system. Somewhere between the charcoal canister and the tank was the cause of the leak.

I’ll share more details when I go to pick up the car, probably Monday, for anyone concerned.

I’m a bit updet at myself for getting so close to spot the problem. Once I added the dye, and saw that dye in my trunk, I immediately assumed it was the tank and took it back to the shop that sealed/refurbished it for me two years ago. I should have taken one more look at the tank with the plate removed to find the actual source…ugh

Unless it’s the short rubber hose connecting to the top of the tank, the line to charcoal canister is behind the tank and is metal and can’t be fixed/replaced without the tank removed. At least on coupes. Is this the same on convertibles?

The convertible fuel line routing is as you describe. Coincidentally I removed the very badly rusted fuel tank from my 1990 XJ-S convertible parts car yesterday. Attached is a picture that I took of the larger fuel return line (circled in yellow) and the smaller fuel vent line (circled in red).

This is how a pre-facelift factory convertible is plumbed. I have no idea if the face-lift cars are the same since they are very different in many ways. :thinking:


It is different. There is a rigid metal pipe that can easily be connected to from inside the trunk.

This metal pipe is continuous from that point on until it peeks out under the car, where the fuel supply and return nipples can be access under the car. Not easy to reach though, but doable, I’m sure.

I did blow air through. From short rubber hose at top of tank to an unplugged rochester valve. It seemed clear.

That metal pipe ends up making an S shape as it goes from inside the trunk to under the car through a small hole. A replacement pipe could have been fished through. I did send a q-tip into the trunk end as far as it would go, just before the bend and came out clean.

I did always get fuel trapped in that line though. Tremendous fuel smell when unplugging the rochester valve, along with a small amount of fuel.