jonnyjr said:What do you mean its stuck? Have you pushed the red sprung leaver to the side fully and tried twisting it? There is a recess inside if you have a helping hand you can push with a stick against the inside of the priming cap and twist at the same time? More than likely the rubber o ring is seized, just try some brute force. Once you do get it off, keep it lubricated with Vaseline.
jonnyjr said:Yes there is a hole going to the inside of the filter canister, if you shine a torch down it you should see a straight piece of plastic going across the diameter of the hole, push on this bit, and twist from the out side of the priming cap.