Had this tree pruned in Autumn, now there is a constant drip of sap coming off it.
Never had this problem before, my car is parked underneath it and it is making a right mess.
Can I do something to locate the branch that is leaking and seal it?
It seems, the sap in your birch started rising particularly early this year!.
I wouldn't have been surprised if it had been pruned in January or February but Autumn is usually fairly safe.
Hopefully the 'bleeding' should slow down soon, when the tree is actively growing, as it starts to leaf up and the wounds should callus over.