Bleeding nuisance - Banana 2.5

[GoBananas]

So
A while back our van ran out of fuel and needed bleeding to get it restarted. It’s a 20+ yr old LDV Convoy with the banana engine.
Got it going, although the issue kept recurring for a few miles of journey and had to be re-bled until it was all good (I thought!)
Had to repeat the process a few times since, but I replaced the return lines because they looked pretty old and perished and that seemed to have done the trick. It was driven 230 miles, left standing for almost a week and then made all but 5 miles of the return journey before the problem resurfaced.
Got it going but it was a struggle to get it through that last 5 miles and the next day it wouldn’t start at all.
I’ve replaced the fuel filter and managed to get close to getting it going - it ran for a while but then stuttered and stopped.

It feels like air is getting in somewhere and I’m thinking my next step is to replace all the fuel lines? But if there’s a quicker more likely solution I’d love to hear it.

Any hints and suggestions gratefully received.

[Altransit]

I seem to remember that the Convoy has rubber connectors on the top of the tank which can perish and let air into the fuel intake side of the pump, or it could be as simple as a blockage caused by muck being drawn into the pipes, due to the low fuel situation.

[dumper]

On the transit set up you could get air build up in the leak off system to cure it you had to change the way it returned to the tank the Ford set up was the return came off number 4 injector you had to remove the rubber leak off bung from number1 and fit it to number 4 injector and then extend the leak off pipe to number 1 so it returned the fuel to the tank instead of number 4

[GoBananas]

On the transit set up you could get air build up in the leak off system to cure it you had to change the way it returned to the tank the Ford set up was the return came off number 4 injector you had to remove the rubber leak off bung from number1 and fit it to number 4 injector and then extend the leak off pipe to number 1 so it returned the fuel to the tank instead of number 4

Thanks for responding.
Assuming that number 1 is the cylinder at the front of the vehicle that mod had been done by a previous owner. I just replaced the pipes.

[GoBananas]

I seem to remember that the Convoy has rubber connectors on the top of the tank which can perish and let air into the fuel intake side of the pump, or it could be as simple as a blockage caused by muck being drawn into the pipes, due to the low fuel situation.

Thanks. I’ll have to get under the van to have a look at that. Would muck in the pipes before the filter be a possibility? More under the van work to check/rectify that I guess.

[Altransit]

Would muck in the pipes before the filter be a possibility? More under the van work to check/rectify that I guess.

It's always possible, you could try blowing back down the pipes from the filter end to clear any possible obstruction

[dumper]

I’ve had problems with the fuel filter before if it’s not pushed up fully home before tightening the clamp it can suck in air on one van I had to take the unit off the so I could push the filter head down onto the filter it’s symptoms was you could start up from cold drive alright then stop turn off the engine but would be very difficult to restart when hot never a problem cold.

[GoBananas]

thanks for all the suggestions

Update - I replaced the fuel filter and it started briefly but then died
Having reached my limits I took it to my favourite garage where I knew that the owner has an affinity for these engines having grown up with them.
They identified some dubious sections of fuel line and replaced them. All is now good. Simple eh?!