Fuel leak, advice please...

Hi,
I was having a few starting problems it would start, then stop then would requiring some cranking before it would fire and run.

So, I took a look and noticed a leak from the filter assembly, I replaced the filter and seals thinking it was a dodgey seal, but its exactly the same.

The leak is where the filter meets the top of the filter assembly, its a 1990 2.5D the one with the 4 pipes coming/going into it; 19J engine.

I ran the engine, and with it running, fuel was running down the side of the filter, emerging from where the top of it sinks into the channel in the assembly. With it running I tightened the top bolt to see if it slowed/stopped the leak, I then loosened it incase it was overtight, but eventully it just got so loose it went everywhere, so at the moment its at the inbetween stage of so tight it causes the seal to distort and therefore leak very badly or so loose it just pours from everywhere.

The leak is not minor either, were talking about a good trail of fuel wherever I drive.

check to see if anyone has left a seal in place from a previous change..just a though as it can happen

A case of a dodgey placed O-ring, perhaps slightly Haynes' fault, and my lack of experience with the bolt together filter assembly.

Cheers for the advice, it led me to a good looking at the gasket, and the flaq of where it was.