Another Jabsco issue

[JSBryant]

I've read allot of threads here pertaining to the Jabsco toilet issues but Im hoping some one can help me with a specific problem that I cant see covered here. Apologies if it has been covered and I missed it.

The toilet pumps out fine all except the last few inches which simply washes back and forth and results in being sprayed back out of the toilet due to the motion the pump creates tying to expel the last of the contents. Its pretty unpleasant. There are no blockages but the pump still will not pump dry leaving this back wash in the bottom that even with the seat down goes all over the head floor. Im about to do a complete rebuild although replacing it all together seems like a better option.

[GordMay]

Greetings and welcome aboard the CF, JSBryant.
This is: Forum Tech Support & Site Help.
You should repost under: Plumbing Systems and Fixtures ➥ http://www.cruisersforum.com/forums/f115/

[motion30]

which particular jabsco head do you have?

[ranger58sb]

Yep, which model?

Could be as simple as needing a new joker valve... and/or maybe the discharge line isn't fully blocked but perhaps constricted enough (as for example, with uric acid crystals) to be affecting the pump action.

But...

-Chris

[svHyLyte]

Originally Posted by JSBryant

I've read allot of threads here pertaining to the Jabsco toilet issues but Im hoping some one can help me with a specific problem that I cant see covered here. Apologies if it has been covered and I missed it.

The toilet pumps out fine all except the last few inches which simply washes back and forth and results in being sprayed back out of the toilet due to the motion the pump creates tying to expel the last of the contents. Its pretty unpleasant. There are no blockages but the pump still will not pump dry leaving this back wash in the bottom that even with the seat down goes all over the head floor. Im about to do a complete rebuild although replacing it all together seems like a better option.

One cannot completely evacuate the water in the base of the toilet. Once the water level falls to the level of the pump intake opening, you simply cannot draw any more water into the cylinder. If the remaining water in the base "sprays" when you're actuating the pump handle in the the "Dry Bowl" position, the weighted base gasket--Part Number 20043-0000--is no longer sealing the base of the pump on the down stroke and should be replaced. Not a big deal. Four screws. Remove the old seal, clean the seat, apply a thin coat of silicon dielectric grease to the rubber of the replacement seal and install that, weight up. The foregoing takes , maybe, 10 minutes, if that. As a routine matter, periodically add a squirt of "Head Lube" to the last few inches of water in the toilet before pumping out and once a month or so, run a gallon of water with 8 oz of Muriatic acid mixed in through the head and you'll be good to go.

FWIW...