Hello,
Thank you for trying to understand what I wrote
. Reading again it is really confusing.
We will try to swap the hoses as suggested.
Just in case, does anybody has a diagram of the pump so we can check the connections.
Also another idea we had that you may perhpas confirm.
We understood that there is a secong pump inside the petrol tank. As the petrol tank has been empty for few weeks, so maybe the second pump is blocked and doesn't allow enough pressure.
Thank you again.