Blocked fuel tank?

[Autobahn]

Restoring a '54 split screen that had not been run for over 10 years.
Engine was started by direct fuel supply to carb after servicing engine and it runs nice on a factory recon 803cc engine.
Petrol tank was removed for welding of boot etc and any old fuel removed and blown out with air line.
Now tank replaced with new fuel but would not supply carb.
New fuel pump fitted but it was struggling and still no fuel?
I left cap of in case it was a vacume problem.
Fuel pipe is ok as it was blown through and fuel is delivered to engine if pick up directly from a fuel can instead of tank.
I connected high pressure air line to tanks fuel delivery outlet but it appears to still be blocked?
Next step is to check inside tank.
Has anyone had this problem?... if so what caused it?

[panky]

I think there's a strainer on the end of the dip pipe in the tank, if it's been re-lined then it could be choked with the material or just full of rust and crap. If it's there then the only way to get fuel through is to try and snap it off through the filler.

[Autobahn]

Could not actually see the end of fuel pick up pipe in the tank through the filler neck, and there is a anti surge plate inside between the pipe pick up point and fuel sender gauge, so unless someone knows different I would say no filter was fitted?

I removed the sender unit and it was siezed in the low position where it had been left for many years without fuel, however the whole thing had about 2mm of hard crud caked on it, which I presume is what has happened over time with the old fuel?

I think the pick up pipe was possibly caked in the same hard crud.
Using a high pressure air line and welding rod poked into the pick up tube from under vehicle it eventually cleared.

There is no sign of any contamination in tank but it does concern me the crud I shifted from pipe must still be in there, even although every effort has been made to blow it out.

Anyway at least it starts and runs now, but the water pump leaks.....