Gas leak.

[r14]

I have 73E w/ MFI. This happens to me twice. When the car sit for over 4 weeks and at the initial start up of engine,I see considerable amount of the gas leak from under the car. Then I turned the car off, cool the car for a while. And I restart the engine to bring to my mechanic,there is no leak at all, therefore we can not find where the leak come from. Do you have any idea what to look? When I keep driving the car at least 1x week,I do not see gas leak even a drop.Thank you very much for your input.

[Mr9146]

Sounds like the fuel lines are rotten. They dry out from sitting and leak when they first get fuel, but they quickly swell up from the fuel and then the leak goes away.

[robmog]

where is the drip? fuel pumps are notorious for leaks too, dry o rings.

[r14]

Thank you guys.
The leak was coming from the bottom of the back seat area and the engine. If this help?

[beh911]

Also check the hard line connections on top of the MFI pump. A lot of pressure there and fuel will show up in the area you describe. So dangerous with the heat exchangers right there so be careful. I wouldn't drive it until you get this sorted

[r14]

Thank you guys again.
Do I need to change fuel pump if the O ring is not good or I can just change O ring?

[robmog]

on a 72 the fuel pump is under the drivers side rear seat.
i think it is the same for 73.
sadly once the fuel pump starts leaking it needs a rebuild or replacement and that is expensive.
not DIY, there are 4 o-rings to replace and it involves complete disassembly.

[r14]

Thank you very much.