I recently purchased a 1986 Catalina 30 and I'm assuming the manual pump toilet is the original, so it's 40 years old. It worked fine for a while, but now after flushing, the waste water slowly fills the bowl back up. Just had a pump out so I know the holding tank isn"t full. Is there something I can easily replace to solve this problem? I believe it's a Jabsco, but have no documents on it.

