Re: 497 sedan
Congratulations on your 'new' boat. From everything I've read on various forums, including the Cruiers Yachts forum, adding the vent filter will only add to your problem; I suggest you don't bother. You can try to flush out the vernt hose. Disconnect the hose from the tank and run water through it from a dockside hose. It should flow clearly. Add some 'good' bacteria to the head and holding tank. I keep a bottle of head conditioner in the head cabinet and add a capful to the head itself after each use. I keep the head side porthole open and have an air freshener on the ledge near the sink. I also leave the side portholes near the galley and the cabin table open so fresh air can circulate. I have screens on all the portholes so birds and flying insects can't get it. Even with all this, there is a slight smell when we enter the cabin after it's been closed for a week or so. Opening the forward hatch and cabin door allows a flow of air, which clears everything. I do plan on flushing out the head and its hoses with fresh water, and then having everything pumped out, just before we haul the boat in a few weeks. Hope this helps. Hy PS. Why don't you join the Cruisers Yachts Forum group and post the question there. Others may have some better solutions.