Anchor lockers often allow water into bilges, adding a good weather stripping should eliminate that. also, how old are your indeck circular hatches, do you open them often, if they are opened on a regular basis, the gaskets should be replaced yearly, if not, every few years, the gasket will crack and allow water in over time, especially if opened up a bit. Also, do you have drink holders in the transom, make sure they are plumbed, and that they are not leaking in there. Check those areas first, if not start from the bow, with a guy washing hard and one guy near the pump and wash until you see water coming to the area where it presently sits, this will narrow down the area where it might be coming from, might also allow you to track it.