Heads won't prime

matt1

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Hi

My Jabsco toilet will empty, but won't flush, particularly after drying out or at the start of the season. The only cure (which doesn't always work) is to cover the inside of the bowl and try flushing. That seems to create a vacuum and prime the heads. Anyone else have better solutions...that work :-)
 
Try pouring some water into the bowl first, always works better for me. I like to keep the water in the bowl and discourage crew from pumping the toilet dry.
 
I do put oil down now and again, if only to stop the squeaking and make it easier to pump but I'll try that to help prime it too
 
My Jabsco toilet will empty, but won't flush, particularly after drying out or at the start of the season. The only cure (which doesn't always work) is to cover the inside of the bowl and try flushing. That seems to create a vacuum and prime the heads. Anyone else have better solutions...that work :-)

It's probably time to replace the rubber valve in the top of the pump. If you undo the 6 screws you can lift the top of the pump off. You'll see a rectangular rubber sheet with 2 weighted flap valves. These can get distorted with age and then won't seal properly. Spares are easily available.
 
I put half a cup of cooking oil down it and pump it before closing the sea cocks and leaving the boat, it seems to keep the seals in good order. That said I also keep a 29042-0000 seal kit on board as it seems to be a service item!

Have you checked you inlet seacock is opening correctly and that it's not blocked??
 
While oil may do something for the outlet it won't deal with the problem of sticking inlet flap valve which is almost certainly as pvb says, the cause of the problem.

Just be careful taking the screws out, and particularly when replacing them by making sure they are engaged in the threads before screwing down. Use only hand driver not a power one.
 
Hi

My Jabsco toilet will empty, but won't flush, particularly after drying out or at the start of the season. The only cure (which doesn't always work) is to cover the inside of the bowl and try flushing. That seems to create a vacuum and prime the heads. Anyone else have better solutions...that work :-)

Sounds like the seals need replacing.
 
The best way to lubricate a Jabsco toilet is to smear the piston with silicone grease. It only needs doing about once a year for average boat use. Putting any sort of oil in the toilet isn't recommended as it can affect the neoprene seals.
 
I'm having similar problems with my toilet. I think it's the seal round the pump shaft. It needs replacing as water leaks out when pumping, if water can get out air can get in so the inductions stroke for the flush water will be poor.
 
It's the little flapper valve in the top. Remove screws and clean/refit, it may start working again.

Failing that, buy a repair kit, around fifteen quid, and it all goes like new again!

I had a few....the 'pouring oil' trick if a waste of time in real terms, you want to repair it, not bump-start it.
 
Thanks everyone. New seals it is then, as it happened immediately after launch when I had checked the seacock carefully so I know that isn't obstructed. Interesting that I started using oil about 3 seasons ago and I would say that coincides with when I first started having the problem. So maybe silicone grease is the way to go. Anyway, I will change the seals! Thanks :-)
 
Remove the white pipe at the top of the pump that feeds the bowl with flush water, hold your finger over the outlet whilst pushing the lever down, then re-connect the white pipe before you pull the lever back up and it will work.
Pouring oil down the pan will oil the outlet (the bit that always works) but will do nothing to help with your problem with flush water unless you connect the flush intake to the oil.
New flapper valves will solve it and are the correct repair, but won't solve this problem with drying for that long.
 
> Putting any sort of oil in the toilet isn't recommended as it can affect the neoprene seals.

We used vegetable oil twice a day for six and a half years, less the odd haul out, and had no problems with the seals.
 
This happens during the winter if it is left in the "dry" position. The weighted flap is then lifted and may not return when required to. The solution is to leave it in the "wet" position. In some boats, this may lead to water entering the bowl, but this can be prevented by closing the seacock or lifting the boat out of water.
 
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