My Jabsco won't suck

[dylanwinter]

I have a long running bog problem

the Jabso will not suck water in

it will expell any water I put in it but will not pull stuff from outside

the inlet through hull was stuck when I bought the boat - so I dismantled it and re-assembled

no sucking - so I assumed I had put it back together wrong

I took it apart at low tide yesterday and it was right - I shoved a tent peg down through the hole and out the bottom of the hull

when I operate the loo in fill mode it is very stiff and there is a sort of sucking noise from the bottom of the bowl

before I wait for the rtide to go out and start the potentially unpleasant task of dismantling it ...... any guidance for me chaps

D

here is a one of the finest pictures I have ever taken

http://www.keepturningleft.co.uk/wp-content/uploads/throne.jpg

 

[charles_reed]

At a guess, the "dry-pump" flap valve stuck open.

 

[dylanwinter]

At a guess, the "dry-pump" flap valve stuck open.

tell me more

why might it be stuck open?

if I shift it does it need some lubrication of some sort

how deep into the bowells of the thing do I need to go to access it

I see that there have been a number of other threads over the past decade on here

the same problem

"pass me the rubber gloves Eugene"

D

 

[jav301]

Quite easy and clean. Undo the top of the pump. 4 screws. you will see the rubber valve assembly. Often the inlet flap gets distorted because it has been left in the dry bowl position. Youtube will show you step by step.

 

[dylanwinter]

Quite easy and clean. Undo the top of the pump. 4 screws. you will see the rubber valve assembly. Often the inlet flap gets distorted because it has been left in the dry bowl position. Youtube will show you step by step.

very funny video

two large yanks a bench and a bog

 

[EugeneR]

"pass me the rubber gloves Eugene"

It's a service kit you need, my friend.

From memory, remove the 4 screws at the top, pull out the top and plunger. Do it slowly and tilt the plunger sideways so you won't spill but allow water to drain down. Remove the rubber gasket / seal with metal bits - if you haven't seen it before, very likely you will need to replace it now. Put some KY on the plunger, insert and it should suck again.

Eugene

 

[charles_reed]

Quite easy and clean. Undo the top of the pump. 4 screws. you will see the rubber valve assembly. Often the inlet flap gets distorted because it has been left in the dry bowl position. Youtube will show you step by step.

Thanx!! for taking the problem of explaining off my shoulders.

 

[FulmarJeddo]

It sounds very similar to when I bought Jeddo. It was a real struggle to get the flushing water through. It did eventually self clear so I put it down to a blockage somewhere in the pipe or valves. The following season the pump went stiff and smelly (don't want to start that discussion again). I stripped it down, cleaned and greased it with silicone grease (from a plumbers shop). Silicone grease is safe for neoprene pushfit seals in plumbing, so safe on the pump valves and seals. It's been fine since.

 

[John 32i]

Hi Dylan, I had the same problem, which was sorted very easily last Saturday morning....just unscrew the top off the pump (6 screws) and remove the top along with the plunger - all I did then was remove the rubber seal (with the two metal inserts) gave it a clean up and reassembled it - I feared it would be a lengthy, unpleasant and possibly costly job but was proved wrong on all counts!!

 

[l'escargot]

Jabsco recommend lubricating all parts with Vaseline/petroleum jelly. It isn't water soluble and doesn't wash off as easily as some other lubricants

 

[Gerry]

To keep everything running smoothly we regularly treat our Jabsco to some 'salad dressing'. A slug of olive oil to keep the rubber well lubricated(!) and a slug of vinegar to keep the limescale buildup down.

 

[Tranona]

Couple of tips for stripping it down. The screws are not self tappers although they look like it, but there are threads in the plastic. Undo carefully with a hand screw driver. When you put them back take a turn backwards and you will feel them drop into the thread. Do up just hand type. The lack of suck, as others have said is the flap valve stuck through lack of use. Just needs cleaning, or better still replacing. The other seals on the piston may also be worn, so worth getting a service kit. The messy job is changing the joker valve in the outlet, but if you have not used it for doing No2s then won't be too bad. The instructions with diagrams are in with the service kit.

 

[Stork_III]

Couple of tips for stripping it down. The screws are not self tappers although they look like it, but there are threads in the plastic. Undo carefully with a hand screw driver. When you put them back take a turn backwards and you will feel them drop into the thread. Do up just hand type. The lack of suck, as others have said is the flap valve stuck through lack of use. Just needs cleaning, or better still replacing. The other seals on the piston may also be worn, so worth getting a service kit. The messy job is changing the joker valve in the outlet, but if you have not used it for doing No2s then won't be too bad. The instructions with diagrams are in with the service kit.

Or fit a new twist/lock pump instead for not much more.

 

[nigelmercier]

Jabsco recommend lubricating all parts with Vaseline/petroleum jelly...

I'm surprised. For rubber you would normally use silicone grease: http://amzn.to/1lmk24o

 

[Vara]

Aaah a job I've been doing today, service kit about £28, and about an hour to strip clean, and replace all the bits, now works a treat. I've always used silicone grease rather than recommended Vaseline as it's less sticky.

Generally need the full kit every three years or so, if it gets a bit sticky in between times a strip down and clean with hot soapy water and a toothbrush usually makes things work better.

Take note of the remark re screws, if ham fisted easy to cross thread and it won't seal.

 

[Robin]

I'm surprised. For rubber you would normally use silicone grease: http://amzn.to/1lmk24o

I used a plainwaterproof grease for years, the same stuff we had in the tool kit for lubricating Blakes seacocks and the like ( made by Duckhams???), I filled the piston barrel with it like filling a grease gun, using a narrow screwdriver to rid the air bubbles and it would last pretty much a season before the squeaking and slight stiffness would reappear.

 

[l'escargot]

I'm surprised. For rubber you would normally use silicone grease: http://amzn.to/1lmk24o

Perhaps the parts aren't rubber. They specifically say "Lubricate pump cylinder bore with petroleum jelly (Vaseline)" online and in the printed manuals.

 

[johnalison]

Jabscos seem to work well or not at all. There must be something basically wrong with Dylan's or it would work, even if a bit stiffly. The usual problem is when the rubber gasket/flap gets stiff and lazy, and then the pump won't prime itself but moves easily. Sometimes the "switch" doesn't move across properly and it won't pump at all. If you have taken it to bits and it still won't work, something needs replacing, there is a blockage or you have assembled it incorrectly.

 

[vyv_cox]

Perhaps the parts aren't rubber. They specifically say "Lubricate pump cylinder bore with petroleum jelly (Vaseline)" online and in the printed manuals.

Trouble is that saying 'rubber' is a bit like saying 'steel'. Other than natural rubber, which is not terribly useful stuff except for tyres in the vulcanised form, there are about a dozen or so base polymers used for 'rubber' applications, with countless ways of formulating each. Most seals in boats will be either nitrile or neoprene, either being specified where oil and water might come into contact with them. Nitrile is usually specified where the oil content is significant, e.g. bilge pump valves and diaphragms, neoprene for lesser oil levels. I believe that most toilet seals are neoprene, although I think I have seen EPDM specified, which has very little tolerance for hydrocarbons (the same rubber that is used for soles of shoes.) The beauty of using silicone grease is that it reacts with almost nothing, in which case it does not matter what the seal is made from.

 

[charles_reed]

Jabscos seem to work well or not at all. There must be something basically wrong with Dylan's or it would work, even if a bit stiffly. The usual problem is when the rubber gasket/flap gets stiff and lazy, and then the pump won't prime itself but moves easily. Sometimes the "switch" doesn't move across properly and it won't pump at all. If you have taken it to bits and it still won't work, something needs replacing, there is a blockage or you have assembled it incorrectly.

We all know that Dylan is "Afflicted of Hephaestus" and that nothing mechanical will work proprerly for him.
Please don't depress him even further by suggesting something really serious is wrong.