Peggy,I have a Jabsco compact head in my Cat 30 which I installed 6 years ago. This past summer it started to malfunction. After flushing via the thru hull (out at sea) the sea water would come back in and fill the bowl to the top. Switch the "Y" valve over to the holding tank and it did not occur. Obviously there is a flapper valve that is gone in the discharge cycle of the head.Question is, should I purchase a rebuild kit or a new head. The cost of the kit (which hopefully has the flapper valve) is $75.00 Canadian and the cost of a new head is $150.00.Since I have never taken the head apart I am leaning towards a new head. Seems like a much easier and cleaner option.Cliff CarterPlusOne C30 #598Oak Bay, B.C.