Jabsco Bog Problem.

BarryH

BarryH

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I have a Jabsco fitted. Don't often use it if I'm honest, I'm a man the World is my bog, well the lee rail to be exact. The daughter was on the boat last weekend and insists on using the bog.
Problem is that it will not pump in sea water. It'll pump out ok, just not in. No great fiasco as I just threw in a bucket of water and pumped it out. Now, before I get covered in **** dismanling the thing has anyone got any ideas?
Already checked the inlet seacock all seems ok there. The little lever on the pump unit seems to give a positive action. Theres no resistance when trying to pump water in. There is resistance when pumping water out, but no more than you would expect. Are these things like 2 stoke engines in that they need to be used and thrashed every now and then?
Not looking forward to sorting this one. Thanks in advance.
 
The standard reply :)

If you leave the lever in the dry position it is bending a flap of rubber. Eventually it takes this shape and when you move the lever to the wet position it does not revert to its straight shape needed to close a valve and allow water to be pumped in. Solution that often works: move the lever to the wet position. Go away. Come back anything between half an hour and a day later and hopefully the flappy bit of rubber will have reverted to its correct shape and pumping in now works. Vigorous pumping helps to draw that flap downwards.
 
Mine was doing this when I got the boat, and I ended up replacing the pump. Depending on how old your Jabsco is there's a new pump design which has a twist lock to stop backflow, and it's definitely worth updating to. Otherwise if the method above doesn't work there's a service kit which is slightly cheaper than a new pump and allows you to replace the rubber bits. Either way it's an easy fix as the Jabsco is a simple beast.
 
The valves do seem to get very annoyed if someone pumps them against resistance because the seacocks are inadequately opened. They do tend to sort themselves if set back to open and left to get the pressure back up. I am constantly amazed how difficult people find it to work the Jabsco on my baot without breaking it, even when I give detailed instructions at the start of every cruise. They either pump like mad despite the cocks being closed and the thing resisting or they put stuff down it that should not be. I must make up a sign that has a numpties guide to the toilet because I dislike taking it apart and spending a day trapped between the mast and the bog.
 
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Fit a new top flap, 5 minutes, clean and easy job. Repair kit around £15-20 from memory, they last two to three years.

Or strip, clean, lube and refit...
 
Does it never pump in seawater or is it the case that it just won't self prime? Mine works fine as long as there's a few inches of water left in the bowl for it to pump out but if I empty the bowl it won't prime itself and start pumping in again. Then it needs a kettle or bladder full of liquid adding and all is well again. I've got used to it so haven't bothered investigating it further.
 
I had same problem as OP when I bought my boat first. After servicing the seized seacock outlet I thought I had cracked it, only to find it still wouldn't work. Solutution - to purchase a service kit and a spare top gasket which I replaced and kept the service kit in stock.Two years later still have spares in stock and toilet works a treat with new rubber top gasket fitted. Gasket has two weighted disc on them to aid closure - one had pierced the gasket causing a split, so no seal.

I do leave a little water in bowl with smelly stuf added to aid suction, and also leave lever in dry bowl mode which shuts off the inlet water still left in the pipe, but never had a poblem with it being deformed and not sealing on re-use.
Suction could also be effected by the rubber valve in pump plunger? - don't worry, not a dirty job to fix 6 screws in and out replace gasket job done.

Just one thing- when you get the spare kit or top gasket you need to tell them what colour handle your toilet has as it is relevent to the year of manufacture
 
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If its like mine Its probably the seal round the piston. Just close the seacocks. Remove the 6 screws and remove the pump piston. Put a rubber band into the seal groove to make the seal a bit bigger and replace. If it makes the pump too tight or noisy try putting a little cooking oil into the bowl and then pump out.
 
Thanks for the Heads up! I'll go and check the Flaps and Rings! No honestly I could be in a pile of poo with the wife if I cock it up and end up spending a pile.
 
Hello Barry, I had the same problem when I got down to my boat at the beginning of this season after launching (whilst, lamentably, busting for the loo), I opened the seacocks, and alas the loo would pump out but not in. I took the inlet pipe off and blew down it (on the recommendation of my shipwright father (rather alarming taking the pipe off of an open sea cock "Its probably above sea level! Stop messing around!" was his sage response, he was predictably right)), bubbles came up outside the boat, meaning it wasn't blocked and the seacock wasn't jammed closed.

I simply put the inlet pipe back on, unscrewed the six screws that hold the pump on, took it to pieces , cleaned it up (where the flappy piece of rubber had become gunked up), put it back together, and presto, good as new. I would suggest just do this, and not taking the pipe off - that wasn't good for my nerves! Good luck!!
 
MagicalArmchair said:
unscrewed the six screws that hold the pump on, took it to pieces , cleaned it up (where the flappy piece of rubber had become gunked up), put it back together, and presto, good as new. I would suggest just do this, and not taking the pipe off - that wasn't good for my nerves! Good luck!!
Click to expand...

+1 Rinsed parts in warm soapy water.
 
pmagowan said:
I must make up a sign that has a numpties guide to the toilet because I dislike taking it apart and spending a day trapped between the mast and the bog.
Click to expand...

Surely it's the relevant numpty's job to do that? :)

Under close supervision if necessary, but it's important that the cost of blockage attaches to them, not you. Like rubbing a puppy's nose in it :D

Pete
 
mrming said:
Mine was doing this when I got the boat, and I ended up replacing the pump. Depending on how old your Jabsco is there's a new pump design which has a twist lock to stop backflow, and it's definitely worth updating to. Otherwise if the method above doesn't work there's a service kit which is slightly cheaper than a new pump and allows you to replace the rubber bits. Either way it's an easy fix as the Jabsco is a simple beast.
Click to expand...

I found that the twist lock is worse than useless. As my holding tank is above the level of the head, only a good joker valve and a flap valve that seats correctly will prevent backflow. When buying a joker valve hold it up to the light. If you can see through it choose another one. The twist lock actually encourages backflow because it presses down on the flap valve and distorts it enough to spoil the seal resulting in the contents of the pipe up to the tank returning to the bowl if the joker valve is imperfect.
 
Sounds like the top flap has stuck down from little use!! Remove the top of the pump, and lubricate the seatings with Vaseline, assuming that the top valve gasket is intact, that should solve the problem. Remember, when redoing the screws, to turn them the wrong way, until you find the previous thread created..
 
Don't forget that when you re assemble to turn the self tappers anti clockwise until you feel a "click"this ensures you don't tap another thread in the plastic,as its easy to strip the thread.
 
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