Jabsco Twist and Lock Manual Toilet

[mickand]

A friend of mine owns a Jeanneau Sun Odyssey 40.3 and has a head issue.
The toilet is a Jabsco 29090.
He changed the pump assembly last year and now has some backflow into the toilet bowl.
The waste hose exits the toilet and rises 18" to the Y valve and from the Y valve it rises another 3" to then outfall into the top of the holding tank.
He installed a new joker valve last week and disconnected the vent hose to ensure that there was no pressure build up, but there is still a small flow back into the bowl.
The boat is 15 years old and he never had a backflow issue until he changed the pump assembly.
The new pump assembly is a later design but was sourced according to the Jabsco website and part number.
Any ideas would be welcomed.

[double u]

handle turned & "locked"?

[mickand]

Yes - handle turned and locked.

[double u]

strange! We have the same toilet & arrangement (3' & all) & no backflow at all. Somehow your piston-rod is too short or for some other reaason is not pressing down enough on the exit valve. Maybe calcareous deposits on the seat of the valve?
(I must say, after 1 rtw with a bucket & 2rtws with a Lavac my expectations for the Jabsco were very low (came with the "new" boat), but it performed flawlessly for 1,5 years of dayly 2-person use)

[Allied39]

Way back when I was a "service provider" I maintained a load of these units.
To be honest I find the Jabsco toilet an awsome value for money item, one of the best I have seen in the marine industry. Value for money item I mean.

Anyhow, having dealt with a lot of these units I found that when installintg the pump assembly it is important to NOT over tighten the four screws that hold it to the base.

I find the best way to install the assembly is to very lightly tighten the screws, and open up the valves , alternately push water through the unit and tighten the screws just enough to stop any leakage.

What happens, if you look at enough of them, is that when the screws are over tightened the assembly squeezes the the rubber check valve out of shape.

This is experience gained over years of servicing these units. I hope it helps.

I do not care to argue or deal with the trolls.

[double u]

"I do not care to argue or deal with the trolls."
???

[SV__Grace]

Originally Posted by Allied39

Way back when I was a "service provider" I maintained a load of these units.
To be honest I find the Jabsco toilet an awsome value for money item, one of the best I have seen in the marine industry. Value for money item I mean.
Anyhow, having dealt with a lot of these units I found that when installintg the pump assembly it is important to NOT over tighten the four screws that hold it to the base.
I find the best way to install the assembly is to very lightly tighten the screws, and open up the valves , alternately push water through the unit and tighten the screws just enough to stop any leakage.
What happens, if you look at enough of them, is that when the screws are over tightened the assembly squeezes the the rubber check valve out of shape.
This is experience gained over years of servicing these units. I hope it helps.

This is a great installation strategy that I will use next time, thanks!

I've had this same situation with my Jabsco and I'm pretty sure it's not the joker valve in the outlet, but the check valve at the pump base, which gets calcium deposits and such over time that causes leakage.

A rebuild kit will include a new check valve. Just be sure to install it in the correct orientation, clean the edges, and follow Allied's protocol for tightening it down (I will next time!)

I always keep a spare pump assembly that includes everything all nicely put together for you and find it easier to swap it out then rebuild as I always struggle to stop the leaks afterward. It's not expensive and one of the reasons I'm a big fan of this toilet, which, as liveaboard cruisers, we use several times a day, 365 days a year, so it holds up to a rigorous workout pretty trouble-free. When the pump piston starts to squeak I lube it with silicon lube.

[Cheechako]

IIRC that's the $100 toilet that's now probably $150. Just buy a new one.
Did that on two boats I bought, didn't even worry if the toilet worked. Bought fresh ones without other's pee on them!
I did buy the piston valve assy for one, it never worked right... and was too expensive anyway.

[bobgarrett]

Yes, replace the flappy valve at the bottom of the pump. Thus is held down by the piston but gradually gets a dent in it top by the rod and ceases to seal.
We reduce this by always leaving the handle slightly up when away from the boat - with seacocks closed of course.

[tilostahl]

I have had all sorts of problems with backflow, and was replacing the joker valve regularly, which always helped for about a week. About 6 months ago I installed a Jabsco in-line check valve (model 29295-1010, I believe) and it's been great. Ask me again in about 2 years how well it has held up.

[Gavino]

I have heard of the same troubles......and it turned out to be the small rubber valve which sits in the top of the Y plastic pipe ....might be worth a looksee at if its 15 years old ...

[NYSail]

I will second the do not over tighten the screws for the joker valve..... snug is what I do. No leaks
And no backflow.

Greg

[Island Time O25]

My experience a bit dated but still probably relevant. I had Jabsco on my first boat and the pump started leaking. Looked into their repair kit and the price was something around $50-60. New toilet was on sale for $79. No brainer. This was like 12-13 years ago.

BTW, of the 4 bolt holes in new toilet (same model) only 2 matched, had to drill new holes in the base. Other than that the replacement was easy peasy as far as toilet replacements go. Significantly less work and certainly less messy then going the kit route. Of the total 5 boats which I owned - 2 Jabscos, 1 Wilcox and 2 Raritans. I found Jabscos to be no less capable then the other "more respected" brands.

[sailorboy1]

Has he checked the vent to be sure it is clear?

Has he pulled the discharge hose out and checked to see if after 15 years it is almost completely blocked up with scale?

Is the tank acturally full?

other than a real bad joker valve those are the cause

[Tetepare]

I have a crack in my Jabsco as described here: https://www.cruisersforum.com/forums...ed-236957.html


Subsequent to that post, apparently the vent got plugged (spider season, you know) at the same time the tank full alert stopped working. Short story, the backflow entered the toilet despite the twist and lock being twisted and locked. So chalk up another item on this Jabsco that doesn't work.



My old Jabsco was great. The new one has had problems from day one.