Fuel pressure releif valve leak

[Jesse R]

Gday all,
I've got a 2006 D40 that's just about to hit 500,000 thats sprung a fuel leak. I've just replaced the turbo and scv valve, along with the fuel pressure relief valve and its leaking a fair amount of diesal. I domt quite understand which way the fuel should be moving if there is any but when I remove the fuel line from the back of the relief valve and there is a stream of fuel coming from the hose, not the valve itself. From my knowledge I thiught if there is too much pressure or a faulty pressure relief valve, fuel would be coming from the valve itself, not the hose connecting to it. My question is, how do I fix it and why is it happening? I didn't have any issue untill after replacing the turbo.

 

[Old.Tony]

I wonder what would happen if the fuel cap was loose and the hose you take off the valve is held higher than the tank (so there's no possibility of the tank feeding fuel to it) ?

Information on this thing is scarce. I've never had a problem with mine, but mine is a little younger than yours (around 385,000km, 2009 model).