oil filter thread

[smudge78]

Can anyone help me with a possible solution to getting the dome headed bolt to screw in to the oil filter as the thread is sticking. It did screw in and out without the spring although a bit sticky. I cleaned both threads with a wire brush and petrol but for some reason it will now only screw in about 3 turns and sticks. I don't want to force it and risk stripping the thread although it is tempting!
Right now I'm tearing out what little hair I have left suggestions gratefully received