Haven't said anything because I have no idea but I think my first step would be to find exactly where along that seal it is leaking. If you hear anything then it's a substantial flow and dye should find it pretty easily. Could it be a torn liner along that metal clamp? I have a bottle of dye tablets used for stream tracing and I dissolve a piece of one in water and use a syringe or for deeper leaks where I can't reach directly, a small garden sprayer with a long piece of auto vacuum hose jury rigged to the squirter. I then tape the hose to a pole and am ablle to inject dye anywhere I want. You may be able to find dye markers at a dive shop or even boil raw beets and use the red juice.
Best I can suggest.
Al