Fuel Problems - 60 series cruiser

Don't have a fuel filter attached to the chassis rail on my HJ61 and so far I haven't had to replace the one on the drivers side of the engine block.

Its getting air in somwhere. I had a simular problem with a lister generator except t had a glass bowl on the fuel filter and ou could see the air mouinting until it started to run rough and cut out. I super tightened all the unions (couldnt get spare o rings etc) and that solved it

The sedimenter (the black tin on the chassis rail) that has a couple of wires coming out of it is the water trap which brings the fuel filter light up on the dash when the water gets in it.
They do rust out due to not being cleaned out regularly.
Is there any dampness or smelll of diesel around it?
There is also two ten mm headed bolts on it one at the bottom (the drain) and one up on the top off to one side (breather). Both of these should have a fibre washer on themto stop air leaks.
I'd reckon it has a pinhole in it and is sucking air or there is an air leak somewhere in the fuel system.
I've repaired a few by soldering the holes up but you can usually pick up a decent one at the wreckers.

Thanks for your responses, I now know where to start looking. I was suspecting an air leak somewhere. I have no idea as to where it may be as there is no sign of any leak, dampness or dust being attracted to anything/anywhere.

My other thought is that the fuel line is nearly blocked somewhere. I have replaced the fuel filter that is on the side of the motor and has no effect.

But, when I used to drain the water trap fuel ran out freely (from memory) and recently the flow seems to be restricted. I may have to pull my fuel lines out and check they are clean.

Thanks

Thanks to all, I will be checking the sedimenter and the fuel return for problems.

The problem is intermittent - or so it seems. It may only be that is is running OK untill it collects enough air to cause the problem.

Thanks for your help. See you on the track - somewhere - sometime