I don't know about fixing the existing hinge.
How about buying a hinge from the hardware store, the kind who a long end on one side.
Then bending it to fit the lip of the grill, drilling a couple of holes in top and bottom of grill and using nuts and bolts to attach the hinge.
^^After reading that and thinking for a minute...a George Foreman does seem like an easier solution.
If you do go propane, Mr Hoddy is right, those little bottles don't hold much and get pricey pretty quick.
How about buying a hinge from the hardware store, the kind who a long end on one side.
Then bending it to fit the lip of the grill, drilling a couple of holes in top and bottom of grill and using nuts and bolts to attach the hinge.
^^After reading that and thinking for a minute...a George Foreman does seem like an easier solution.
If you do go propane, Mr Hoddy is right, those little bottles don't hold much and get pricey pretty quick.