Easiest way to find and patch a slow drip in a fuel tank?

[PanzerAce]

So I've noticed recently the smell of gas around my Z, and after I filled up this morning, I found a small puddle in the dirt under it this afternoon. It seems to be underneath the fuel filler cap, so I don't *think* it is an imminent danger, but does anyone have an easy way to find where it is leaking from? Only idea I have come up with is shine a powerful light in at dusk.

 

And is there any way to fix a fuel tank without removing it, draining it, etc?

[chrism]

I had a small pin hole in my tank, self induced. And I used liquid metal to fix the problem. I had to drill the pin hole out a tad bigger and clean the metal aroung the hole. The liquid metal pushed into the hole and bonded to the tank. I haven't had any leaks since then.

[PanzerAce]

You have a brand name by any chance? Liquid metal on google turns up some WEIRD stuff

[TimZ]

You have a brand name by any chance? Liquid metal on google turns up some WEIRD stuff

 

I think it also goes by "JB Weld".

[Mike kZ]

I used this stuff called Sonic-Weld. It's a steel reinforced epoxy putty, made to repair gas tanks. I got it at NAPA. It's in a small plastic tube.

[zcarnut]

.. It seems to be underneath the fuel filler cap, ....And is there any way to fix a fuel tank without removing it, draining it, etc?

 

I had a 240Z that developed a leak in the rubber filler-to-tank tube. I was able to patch it with some gas tank putty/epoxy but I had to drop the tank to get to it. Once you remove the gas tank you can do some maintenance on it, as dirt can build up on top of the tank which retains moisture and promotes rusting.