Back flowing electric toilets and fix

Both my quiet flush jabsco toilets have leaks waste in to the bowls basically since I got the boat. This is the most annoying thing since the holding tank leak. I purchased the minor service kit for my electric toilets and swapped only the joker valves. This wasn't so bad.
First, put a lot of fresh water in the bowl and flush it. Jeanneau actually has what seems like a good design here. They use a second joker valve above the standard toilet one. This is supposed to lower the pressure on the toilet joker but also means when you disconnect the hose at the toilet then you don't get the whole pipe contents spilling on the floor.

Anyway to cut a long story short, the valve were pretty easy to swap out but a little boat yoga is required as the screws are tricky to get at. The replacement joker valves worried me as I'd read that if you can see any light through them at all then get them replaced but both jabsco and Defender.com both said that's rubbish and I gotta say after 2 weeks of using the valves that I could see through that they are right. The toilet backflow is much improved. The valves I took out had maybe 1/4 inch of a gap, and the new ones looked much better.

The toilets basically are fixed. I come back to the boat now and the toilet water is the correct color :)

Standard valve on bottom.

Aft toilet

First haul out

I hauled out the boat before the winter rush. The dealer came and repaired the forward holding tank release valve. I had the anodes replaced and the bottom painted with Pacifica Plus. The marina service yard did that work. You cannot paint the bottom yourself in New Jersey, you need a license.
Total cost was 1900 US for this. I'm planning on leaving the boat in the water over the winter and staying on it a little and sailing when I can.

Toilet fills with sea water on a sail, no anti-siphon valves on toilets.

We did a nice sail on Saturday, our first proper sail with the boat. It went pretty well and when we got back, we noticed a lot of water in the forward head and the toilet was full to the brim with sea water. We know it's sea water because the holding tank is empty given the leaking issues I mentioned earlier.

It appears the our boat has no anti-siphon valves on either toilet. So, when its heeled over, water is basically sucked inside the boat from the sea water flush inlet (the electric toilets use sea water for flushes) and into the toilet which overflows in to the boat. Boats have actually sunk this way and the manual for our toilets insists on requiring an anti-siphon valve be installed which Jeanneau seems to be ignoring.

There is a sea cock to close the inlet which we'll need to do but it blows my mind that Jeanneau doesn't fit these standard on their expensive sail boats which are ocean rated. I've asked the dealer if this was a mistake during fitting or if Jeanneau really ships the boats with no anti-siphon valve. This basically means if you want to use the head at sea then you need to open/close the valve or use fresh water from the shower to flush the toilet. We have a head on port and starboard so we could use the high toilet to avoid any water coming in during use.

Anyway, annoyed.