Tourer fuel cooler woes

[podge]

Hello out there again😀I know I have not posted for quite a long time but I am still here and a happy Tourer owner ( the second one now). Now,the car has a small weep of diesel from the fuel pipe that runs in the hot fuel return line,from the restrictor to the top of the fuel cooler.I have dropped the whole assembly,fitted new fuel hose and double clipped the pipe where it fits to the fuel cooler elbow.The cooler elbow has no cracks,yet at tickover,a small weep of fuel is still appearing from the pipe under the clips. There definitely seems quite a pressure in that short pipe run,is this normal? I am wondering if there is a blockage somewhere.I think it has been doing this a long time now.The car is a 2003 pre facelift and now up to 48,000 miles.

[Kearton]

If the cooling radiator, its exit pipe or both have a restriction, it would cause the pressure in the input hose to increase. I suggest checking those first.

I'm not sure of the pressure at which that part of the system should work, but if you suspect the cooling radiator, an air conn. repair place may be able to check it for leaks, and the flow-through capacity for you.

[podge]

Thanks for that,I am suspecting that little bI metal valve at the moment.I have found a good BMW part number for it ,though a different car,the same engine and setup.The leak is getting worse since replacing the hose that goes from the top of the cooler to the connection on the restrictor,proper hose clips too.Ihave a secondhand complete assembly “ intransit” and may well swop the whole lot over,so I can disassemble mine.That valve has two inlets on one side and one on the other. I suspect the two are in a loop and once up to temperature,the fuel is switched through to the single to the cooler.I had thought of bypassing it witha three way connector to see if it stops the leak,though that would switch the fuel straight through the cooler.