Last week I had some time to finally look at a problem I was having with the head on my boat. It seemed like every time I flushed it there would be a lot of bubbling back in the bowl and the second hint was that I could not get the holding tank to more than half full.
The vent hose is 3/4" and exits out the side of the boat with a small chrome cap with two holes in it. Those holes are covered with a very fine mesh. I took a screw driver and pushed a hole in the mesh and heard the sound of air rushing out. I would guess that salt spray clogged the vent to the point that no air would pass through it. If you get a chance, check out the vent on your head to make sure it is passing air properly.
Denis
The vent hose is 3/4" and exits out the side of the boat with a small chrome cap with two holes in it. Those holes are covered with a very fine mesh. I took a screw driver and pushed a hole in the mesh and heard the sound of air rushing out. I would guess that salt spray clogged the vent to the point that no air would pass through it. If you get a chance, check out the vent on your head to make sure it is passing air properly.
Denis