Wanting to make some improvements to my sanitary system, I looked in all the nooks and crannies to trace the sanitary hoses. I noticed something that seemed odd that I hadn't noticed about 10 years ago when I replaced hoses or even a few years ago when I replaced the y-valve. I've recently had problems with the pump valve which allowed wastewater to leak back into the bowl after flushing. I was surprised by the amount. Mind you, our waste system gets extremely light use.
As it turns out, the discharge hose from the toilet makes a loop about 5' long to the y-valve. From there, one port leads directly to the overboard discharge with no ventilated loop. The other port makes a vertical rise with newer hose to the ventilated loop and down into the holding tank. I've looked in numerous diagrams and they all show a ventilated loop above the overboard discharge and none between the toilet and the tank. Has mine been connected wrong all this time?
Before anybody thinks that I reversed the hoses, I don't think that's possible. First, I never changed out the overboard discharge hose. It's still the black-walled Shields S-101 that the boat came with and the hose isn't anywhere near long enough to connect to the ventilated loop. I changed out the other hoses with white vinyl Shields S-148 and followed the original configuration as far as I can tell. I also replaced the v-loop and it is in the original location.
I have always had a very slight odor problem. It is noticeable when I first open the boat but dissipates with ventilation. I've always been troubled why I can't get rid of it completely. Is the fact that the tank is connected to the v-loop part of the answer? I think the amount of water backing into the bowl is more explainable. There is probably at least a 6' column of water in the 1.5" hoses below the loop. That's about a half gallon, not enough to overflow the bowl but enough to fill it substantially.
As it turns out, the discharge hose from the toilet makes a loop about 5' long to the y-valve. From there, one port leads directly to the overboard discharge with no ventilated loop. The other port makes a vertical rise with newer hose to the ventilated loop and down into the holding tank. I've looked in numerous diagrams and they all show a ventilated loop above the overboard discharge and none between the toilet and the tank. Has mine been connected wrong all this time?
Before anybody thinks that I reversed the hoses, I don't think that's possible. First, I never changed out the overboard discharge hose. It's still the black-walled Shields S-101 that the boat came with and the hose isn't anywhere near long enough to connect to the ventilated loop. I changed out the other hoses with white vinyl Shields S-148 and followed the original configuration as far as I can tell. I also replaced the v-loop and it is in the original location.
I have always had a very slight odor problem. It is noticeable when I first open the boat but dissipates with ventilation. I've always been troubled why I can't get rid of it completely. Is the fact that the tank is connected to the v-loop part of the answer? I think the amount of water backing into the bowl is more explainable. There is probably at least a 6' column of water in the 1.5" hoses below the loop. That's about a half gallon, not enough to overflow the bowl but enough to fill it substantially.
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