Sticking shutter?

I have an old 90mm Angulon (Copal #0 shutter) that I haven't used in two or three years. I got it out today and found that the shutter is permanently tripped -- it fires as soon as you released the lever that cocks the shutter. Is there an easy fix? It had never done this before (when I was using it regularly).

Thanks.

Sometimes exercising an old shutter will help in the short term. I have several that I do that with before using. Yours sounds like a lever is stuck inside which causes it to fire as soon as cocked. Probably an easy fix but if you don't know the internals of a shutter a CLA is worth the cost. Not that expensive, the last one I sent in was only $55.

FWIW -- Cocked the shutter over and over and ... voila! It's working. Whatever was stuck, isn't. Perhaps I'll not let it sit unused for five years.