I've had the diaphragm checked I think mate is that where you take the oil cap of and the noise doesn't persist? This noise is a clacking noise at first I thort I may have snapped an internal because of the severity of the noise and loss of power. Good question aswell I'm unsure. He just said the timing was out and needed to no how they where correctly set up. Has anyone got this info? As then we can rule that out thanks for your reply