Holding tank pump problems

[Chris_Robb]

Since I installed my holding tanks in 2010, I have had nothing but problems with the pump out system, which is a Jabsco tyoe diapragm pump with jocker valves. I am now onto my third pump, as none of the pumps have ever managed more than a weeks pumping without stripping down cleaning and rebuilding- not a job you want to do every week!

So first likely problem from Jabsco - jockers done up too tight. Tried all pressures - makes no difference.

When the pump fails to prime (DIp tube of approx 500mm into tank bottom.) I take it to peices and the jocker valves are not tightly sealed but slightly gaping. The effect at the suction end is to get a suck puff suck puff situation, which should of course not happen.as the jokes are just not sealing (I have tried many new ones.)

So what should I now fit. The Jabsco macerator has a max priming head of 600mm. It would fit in the area with some new piping as it discharges into a smaller bore.

I am not happy with Jabsco at all as they have been extremely unhelpful apart from new pumps which dont work!

 

[charles_reed]

Try these people.
They are specialists in this corner of the market, unlike Jabsco who are now a consumer arm of ITT and uninterested in being special at anything.

http://www.wastecorp.com/marine-pumps.html#.Vb2sTfli1ZM

 

[Chris_Robb]

Try these people.
They are specialists in this corner of the market, unlike Jabsco who are now a consumer arm of ITT and uninterested in being special at anything.

http://www.wastecorp.com/marine-pumps.html#.Vb2sTfli1ZM

Hi Charles. Blimey, have you seen the size of them!!!! Cant find on a quick initial look any yacht size and not needing 3 phaze! I will look further later.

 

[vyv_cox]

Chris, I cannot quite picture your arrangement. The joker valve needs to be at the bottom of a column, where the head of water keeps the lips closed. It can sometimes seem when inspecting a valve in air that the lips are open but it should not be the case when installed. I take it you are certain that the joker valves are Jabsco ones? I recently bought one that was not and found its flange dimensions different, so it leaked.

The ultimate solution would seem to be to fit a diaphragm pump such as the one used with Lavac toilets (forget its name) but it needs space and might be costly.

 

[steveallan]

Henderson mk5

 

[Chris_Robb]

Chris, I cannot quite picture your arrangement. The joker valve needs to be at the bottom of a column, where the head of water keeps the lips closed. It can sometimes seem when inspecting a valve in air that the lips are open but it should not be the case when installed. I take it you are certain that the joker valves are Jabsco ones? I recently bought one that was not and found its flange dimensions different, so it leaked.

The ultimate solution would seem to be to fit a diaphragm pump such as the one used with Lavac toilets (forget its name) but it needs space and might be costly.

Well, that might explain it, though the instruction explicitly say it can be mounted horizontally! I have even sent photos of the installation which they say is correct. But what you say, makes a lot of sense.

I will have to change the instalation with several 90 degeree bends to get the unit in a vertical in a vertical position. I will look at that and see of its possible - I just dont like 90 degree bends in a sewage pipe!!!!

What do people think of the Macerator by Jabsco? is it reliable?

 

[Wino]

Chris, I also do not quite understand why you are getting these problems, my Jabsco Diaphragm- mounted vertically - has been working fine, for the last 5yrs - did leak once but that was due to a worn diaphragm, since then a new service kit every year, no problems- one point, you say you will need 90' bends, why? You should be able to install it with flexible hose (white ) Also as Vyv Cox says it must be mounted in such a way that it is always full of liquid, the weight of which keeps the top joker valve closed.
I hope this helps, wino.

 

[affinite]

Chris
Ive used a macerator to pump out my holding tank for 10 years.
(Although a gravity emptying tank would be my preferred choice, I dont have the space below the tank and anyway, I like the idea that any waste dumped at sea is macerated before dumping.)
I got through 2 Jabsco macerators in 5 years with failed seals/rusted up bearings before buying an ebay "budget" make off ebay.
The budget one was half the price and I figured I could therefore afford to replace it twice as frequently.
Funny thing is the Chinese copy hasn't yet failed. (4 years)
Regards
Steve

 

[DaiB]

I had a Jabsco macerator but after it failed I fitted a Henderson Mk5 hand pump which worked fine. Since then I have arranged a seacock below the tank and it now empties by gravity.

 

[charles_reed]

Hi Charles. Blimey, have you seen the size of them!!!! Cant find on a quick initial look any yacht size and not needing 3 phaze! I will look further later.

They actually produce a manual "bilge pump" essentially a diaphragm pump. The whole of their range is not shown on their website and getting in touch by phone or e-mail, might be worthwhile.
They do, of course, make complete shoreside pump-out facilities.
I do have, in my 25 year-old sea toilet, a joker valve, in the horizontal palne. Providing it's changed every 5-6 years it works well. Just about all the other parts of the toilet are more troublesome.

 

[Chris_Robb]

Sorry, dont know how to get a bigger picture in here! Let me know how to get a bigger picture in and I will! oh just seen lots of attached thumb nails below!

You will note that the tank and pump are horizontal, looking down on the tank. (Jabsco agreed that this was a good way to install). You will note that there is no room above but quite a bit below - this is under the port forepeak berth. To mount the pump vertically would mean getting some pretty severe bends in it- hence I would propose using preformed 90 or 180 degree bends as even flexible hose will not bend that much.

I get the picture that Jabsco dont know about their own products - and that instead of the blurb on their sales - mount at any angle - they should say mount vertically - as that makes more sense.

Question: what happens to hard bits like a cherry stone for instance? that was the cause of the last failure, or is that to be expected?

 

[Chris_Robb]

Chris
Ive used a macerator to pump out my holding tank for 10 years.
(Although a gravity emptying tank would be my preferred choice, I dont have the space below the tank and anyway, I like the idea that any waste dumped at sea is macerated before dumping.)
I got through 2 Jabsco macerators in 5 years with failed seals/rusted up bearings before buying an ebay "budget" make off ebay.
The budget one was half the price and I figured I could therefore afford to replace it twice as frequently.
Funny thing is the Chinese copy hasn't yet failed. (4 years)
Regards
Steve

Steve I will explore the vertical mounting before I move to a macerator - but they do not seem to have a good reputation.......

 

[Heckler]

p

View attachment 52906
Sorry, dont know how to get a bigger picture in here! Let me know how to get a bigger picture in and I will! oh just seen lots of attached thumb nails below!

You will note that the tank and pump are horizontal, looking down on the tank. (Jabsco agreed that this was a good way to install). You will note that there is no room above but quite a bit below - this is under the port forepeak berth. To mount the pump vertically would mean getting some pretty severe bends in it- hence I would propose using preformed 90 or 180 degree bends as even flexible hose will not bend that much.

I get the picture that Jabsco dont know about their own products - and that instead of the blurb on their sales - mount at any angle - they should say mount vertically - as that makes more sense.

Question: what happens to hard bits like a cherry stone for instance? that was the cause of the last failure, or is that to be expected?

Im sure someone else has thought the same thing, where did the stone come from?
S

 

[affinite]

p

Im sure someone else has thought the same thing, where did the stone come from?
S

They have Cherries the size of Peaches out in Greece you know.
Brings tears to the eyes !

 

[Chris_Robb]

p

Im sure someone else has thought the same thing, where did the stone come from?
S

Bit of a bummer I am afraid!

 

[Artic Warrior]

Chuck ya Jabsco away and fit LAVAC LAVAC LAVAC,,,,,,lavac bogs are the best,,,,,,nothing goes wrong with them and they maintain the smell
because they have a seal on the seat lid,,,,,,,the rest are sh,,,,,t....pardon the pun !!....fit the mk 5 pump and your away

Chris, I cannot quite picture your arrangement. The joker valve needs to be at the bottom of a column, where the head of water keeps the lips closed. It can sometimes seem when inspecting a valve in air that the lips are open but it should not be the case when installed. I take it you are certain that the joker valves are Jabsco ones? I recently bought one that was not and found its flange dimensions different, so it leaked.

The ultimate solution would seem to be to fit a diaphragm pump such as the one used with Lavac toilets (forget its name) but it needs space and might be costly.

 

[vyv_cox]

Chuck ya Jabsco away and fit LAVAC LAVAC LAVAC,,,,,,lavac bogs are the best,,,,,,nothing goes wrong with them and they maintain the smell
because they have a seal on the seat lid,,,,,,,the rest are sh,,,,,t....pardon the pun !!....fit the mk 5 pump and your away

The problem is with the holding tank, not the toilet. Wouldn't make any difference what type was installed.

 

[Chris_Robb]

The problem is with the holding tank, not the toilet. Wouldn't make any difference what type was installed.

Having now been in contact with Jabsco, they insist that the installation is correct (ie Horizontal) and that it should work and is designed to work like that.

So I have asked them to provide a fix so it does work like that....... Actually I think you and others are right - that it must be mounted vertically. It really pisses me off that a manufacturer doesn't know what his equipment can do, I have asked them to do some proper tests to prove that it does work to stop them mis selling to others Lets see if they will.

If I do re install vertically, do you think that the pump could be free floating on its pipe connections. Its otherwise going to be quite difficult to mount is anywhere and have room for the pipes? Also, if shit is going to sit permanently in the bottom section, will there be a smell problem with the pipes?

 

[vyv_cox]

My first try would be to add a loop to the hoses, leaving the joker valve where it is. This would provide a head of water(!) that should hold the lips closed. On my toilet the joker valve is installed almost vertically but inverted, i.e. with the lips pointing downwards, but there is a head of about a metre above after a sharp elbow.

There is no smell at all with mine using Tek Tanks hose but the joker valve does have a tendency to salt up more frequently than it did with the old toilet. HCl dosing fixes it but this might be more difficult in your case.

 

[Chris_Robb]

My first try would be to add a loop to the hoses, leaving the joker valve where it is. This would provide a head of water(!) that should hold the lips closed. On my toilet the joker valve is installed almost vertically but inverted, i.e. with the lips pointing downwards, but there is a head of about a metre above after a sharp elbow.

There is no smell at all with mine using Tek Tanks hose but the joker valve does have a tendency to salt up more frequently than it did with the old toilet. HCl dosing fixes it but this might be more difficult in your case.

Vyv, not quite sure on what you are saying. From the pictures in no 11, there is not much room either side. So would you take the input side from the tank, and plunge it straight down and then up to create a sump?

If I can free mount the pump (just using the stiffness of the hoses) then there are a lot more options open. I can not see why this could not be done. This would then be easy to have a R angle from the tank going down, and then mount the pump vertically on the loop created. this would effectively create a sump in the piping before and below the input joker.

Jansco say they are going to run some proper test again to prove that it should work as I have installed it. We shall see....