How to extend the life of Jabsco joker valve

Calif. Ted · Sep 23, 2014

Emily, the valve is a slit in a piece of rubber, with the sticky nature of the "materials" being passed thru said slit I think it more likely something is fouling the slit.
If you try using some head lube whenever your leaving the boat for a few days it seems to help them stay pliable and working well.

Kings Gambit · Sep 23, 2014

The ones on my boat appear to fail due to accumulation of scale deposit [at the slit] from seawater flushing. You might slow this down by purging with fresh water daily while in use; but especially when the boat is "put away" at the slip. Also, Jabsco has a new pump assembly that locks down the pump in place and that is supposed to stop back fill even if the Joker does not close fully. I installed one on each of the two heads on my Bavaria.

Stu Jackson · Sep 23, 2014

Some white vinegar has also been suggested by many to keep the valves "lubricated" and to break down build up in the lines and the valve.

Rick D · Sep 23, 2014

I don't think active use is a problem as much as little use which results in build up. Follow Peggy's advice about flushing a cup of vinegar through the head, let it sit a few minutes and then flush it through; don't let it sit in the lines for an extended period. However, that is a treatment of prevention, not a cure. If I recall, your heads pump up to the holding tank and the overboard discharge is gravity, right? If so, you have the same issue I do on my aft head which pumps up about two feet plus to a vacuum break, there because of a Y-valve and overboard discharge. So, even with a lot of dry strokes, there isn't enough pressure to purge the upward line and we do get some back fill. Nothing to stop it. The twist lock pump is no better in that regard based upon my experience with two. I think Jeanneaus have an anti-backflow valve in the later, larger models. However, I think that could cause its own set of problems. We have learned to live with it. Good luck.

thinwater · Sep 23, 2014

Better yet, switch to Raritan PHII joker valves in the jabsco manual head (they are interchangable). They are MUCH more durable. The slit must be vertical and the bolts must be tightened evenly. This should get you ~ 2 years.

I would NOT flush oil (mineral or veggy) in a Jabsco head as a rule; the internals, including the joker, are neoprene and not very oil resistant. It softens the lips, helps for a few weeks, and then it gets. In moderation, some folks get a away with it. Better, lube the pump according to the manual with synthetic grease, annually.

No, it is impossible to over flush. Under pumping, which can leave waste in the line, is a much greater problem. About 2 strokes per foot of discharge line (write the number on instructions on the wall for guests).

Stu Jackson · Sep 23, 2014

tw, wasn't there a link to a study that someone, perhaps PS did, that discussed this idea in great detail? Do you have that link? Had to IIRC with the materials they were made of, and they both fit properly.

PS You do that final pump through on dry bowl anyway, so you're not overfilling the holding tank, just assuring that the solids or liquids get all the way to the holding tank and don't sit in the valve or lines.

thinwater · Sep 23, 2014

Stu Jackson said:
tw, wasn't there a link to a study that someone, perhaps PS did, that discussed this idea in great detail? Do you have that link? Had to IIRC with the materials they were made of, and they both fit properly.

PS You do that final pump through on dry bowl anyway, so you're not overfilling the holding tank, just assuring that the solids or liquids get all the way to the holding tank and don't sit in the valve or lines.

Yes, PS

(reports Rairtan valves lasting >2x)
http://www.practical-sailor.com/issues/37_44/mailport/Mailport-August-2014_11470-1.html?page=3

http://sail-delmarva.blogspot.com/search?q=joker

BJV · Sep 25, 2014

I help people remedy head aches and have found lately that the Jabsco Jocker valves are not closing fully which allows seepage back into the bowl, even when brand new. Have measured the Raritan Jocker (C253) and believe it can replace the Jabsco one and probably work better.