If there is a concern that the yeast may be on the diaphragm, why not simply toss it, and get a new diaphragm? This seems like the simplest solution, and then you can start using it, and if the yeast problem is still present, then you at least know that the old diaphragm possibly harboring yeast is not the problem.You may still have a yeast prob., but at least you can focus on other sources, and not the diaphragm anymore.(talk about redundancy!) Ellen