Toilet backfilling with waste

ButtercupWa

Member
Joined
Jul 24, 2020
Messages
23
Fluid Motion Model
C-28
Vessel Name
Buttercup
Hi! First time boat owner, so would appreciate some help! I own a 2018 Cutwater 28

The toilet flushes as expected, but when I check back later the bowl is almost completely full with waste water. I've seen videos recommending changing joker values on Youtube -- the pros demonstrate it with toilet sitting on a tabletop, oh so easy -- but then I saw someone do it in real life, did not look so easy.

Any advice? Thanks in advance.
 
First of thing, check that the vent from your waste tank is clear. There have been a number of posts on the subject recently referring to waste odours but you may just have the ultimate result of a blockage. If you’re building pressure in the tank it could be forcing waste back. Undoe and remove the inspection port, flush the toilet and see if the problem still exists. If it does you have eliminated possible cause. If not, check the vent.
 
I had a C-28 with a similar problem. The backfilling of wastewater is related to the joker valve. I have replaced it in place. NO need to take the toilet out. It takes about 20 minutes, and while a bit nasty It is not difficult.Remove two bolts and pull the housing out. Replace with new joker valve. re-insert the two bolts and tighten down. Before you start, Most importantly you should pumpout your holding tank, then fill with water and pumpout again. Also flush your toilet for 10 seconds to move as much wastewater out of the line and into the holding tank. On my C-28 I do wonder if the holding tank inlet was a bit higber than the toilet as it does drain back to the bowl basin. I have not had any problem at all with my R-29
Wear gloves, and good luck
boaterjoe
 
Thank you Chimo and Boaterjoe for the quick and informative replies!!

Apologize for the followup questions, combination of first-timer and the Cutwater Owners Manual lacks so much information.

Chimo, In the C-28 I believe the waste water tank is right inside the doorway, what would the inspection port look like?

Boaterjoe, how do I find the make and model of the joker value I need?

Thanks again!
 
Assuming you have a Raritan head (Sea Era) the Joker Valve can be purchased at a number of online distributers. West Marine and Amazon to name a couple. Boaterjoe I believe has the fix and follow his directions. I would go a step further. Close the sea cock for raw water flush. Then fill a bucket with fresh water start flushing the head while pouring the fresh water into the head. Fill the bucket again and flush again with fresh water. This assures all waste is cleared from the 1 1/2" hose going to the waste tank and the water that drains back is fresh water.(I have fresh water flush and still use the bucket flush to assure I have flushed enough clean water through the system) Have some shop towels ready or a roll of paper towels and the bucket ready foe town disposal. When you remove the elbow retaining the joker valve the waste hose is going to start draining, divert the clean fresh water to the shower drain and sump. Use the paper towels to collect any debris that comes out so it doesn't go into the sump. That was the hard part the rest is easy reassembly.
 
The holding tank on the C28 is under the rear reversible seat. Flip the seat back and lift up the lid. There are two inspection ports there. You can see the holding tank better from the port port. lol, that's kinda funny.
 
The waste tank has been in a couple of places on the 28. In your 2018 it is most likely in the spot that you suspect, port side, right inside the door under the hatch.

I have seen a couple of 28's where the routing of the waste hose has contributed to the backflow into the bowl. In one case it was necessary to reroute the hose by lowering it and then ensuring that it had a high loop prior to going to the head. There is also a waste line check valve that can easily be installed in the line after the loop. What is backflowing into the bowl is the contents of the line before it reaches the tank.

You can access all of the line by removing the wall panels in the cave. If it all runs along the top of the space you might benefit from lowering it so that there is not so much "fluid" above the level of the bowl.
 
I believe joker valves are all the same size for the most common types of toilets. Available on Amazon for $21.00 . I also agree with jagizzi"s comments regarding the placement and height of the wasteline on the C-28. They do tend to drain back to toilet unless you interrupt the slope.
good luck
 
Lots of good information.

To avoid any partial backflow when putting in a new joker valve, do a pump out first. Changed mine twice and no inside mess.
 
I second the recommendation to first check the vent - I had a clogged vent line a few weeks ago and after blowing it out as recommended in some posts here on tugnuts - no more backflow to toilet.
 
I love the Tugnuts Forum, fantastic advice -- thank you all!!

I looked under the panels and found some off the components mentioned, but not others. So I'm thinking for the first time I will hire someone to make the change and watch/learn it being done.

Any recommendations of a person that works in Lake Washington that I could hire?
 
You’re at Newport...I’d start with Seattle Boat. They can service the boat at your slip. See PM-Dave
 
2012 Cutwater28 I got only 8 years out of the joker valve. Same problem bowl filling up.when I went to buy the valves I could not find them anywhere. Finally found online and three days later my order of 2 arrived. I now have a spare behind the mirror in the head.money well spent.
Stuart

Btw after all was done I sprayed the area with bleach.
 
Thought I'd give an update on my posting.

Had someone come out to fix the head, unfortunately due to Covid I couldn't be on the boat and watch over there shoulder and learn how to replace the joker valve. Fortunately, the replacement of the joker value did the trick, head working well now -- no backfilling. Had them clear the vent as well per your recommendations.

Thanks for all your help!
 
Good posts...going out to change mine right after I finish my coffee. Seems like a post breakfast job. Did the pump out and fresh flush yesterday.
 
Is it possible you're not pumping the waste all the way into the tank? A couple pumps with water to clean the bowl, switch to dry and pump several more times to move everything into the tank.
 
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