Automatic Bilge Pump Trouble - 42DS

[andrewtas]

Hello brains trust. Hoping that I might identify a better solution than upside down with a sponge and a bowl of dirty water...

When switching our bilge pump to auto with a little water in the bottom of the bilge, the pump motor (behind the settee adjacent to the fresh water pumps) operates, although no water is removed (looking at both the bilge and overboard outlet). The water is a little murky, but no sediment to block anything. The inlet hose is not blocked. Even if it’s an issue with the float switch, it’s in the “on” position to have the pump operate.

What next? Remove the pump to see if the impeller has failed? Pay somebody that knows what they’re doing? Have another coffee and get back to it with the sponge?

[timpeacockuk]

It could be the diaphragm in the pump itself. Ours failed last year with similar symptoms. You can buy a replacement part for the Johnson pump, but I found it was very expensive and not far off the price of replacing the whole pump, which is what I did in the end.
Not a cheap pump, but cheaper than dealing with the consequences of not replacing it!!

[Mistroma]

I assume you mean the bilge sump and not just the bilges. The pump you are talking about lifts water from the bottom of the sump but leaves a fair bit behind. There's a problem if the sump remains completely full and could be problem with the diaphragm or valves.

Could you confirm that you have poured enough water into the sump to almost fill it? It is possible that something fell into the sump and blocked the inlet hose.

I can't remember if the bilge pump is easy to remove but would try to disconnect the inlet hose. This would allow you to test for a blocked inlet hose and pump operation using a water hose. A bit of pressure on the inlet hose should blow a blockage back to the sump. Pressure on the pump inlet would prime the pump and possibly clear debris from the valves. The pump should self-prime but a damaged diaphragm or blocked valves would prevent priming.

Be prepared to remove the pump if the problem remains as a damaged diaphragm would allow water into the internals and cause corrosion.

[sitara]

The rubber flapper valves in the bilge pump can sometimes not close properly. I have had this problem a couple of times. The first time the metal plate holding the rubber strip in place appeared to have been screwed down too hard deforming the rubber, and the second time the rubber appeared to have expanded preventing the flap from closing properly.  In both instances the out of placement error was small but resolving the issue fixed the problem. I also added a foot valve in the bilge although not sure if this was necessary.

Getting to the pump in the 36i is a bit of a pain, so I hope you have more room in the 42DS.

Cheers

Rob

[Trevor]

Hello andrewtas,

The diaphragm pump is not good at handling any small pieces of debris. I have had cases where the pump has a small item opening the inlet flapper valve and another where a small item was holding open the outlet flapper valve. I know this certainly indicates I should attend to my less than pristine bilge! I think on the outlet side of the pump there is a choker valve as well. If the valves are held open by the debris the pump just will not work. It is not hard to disassemble but getting it out from behind the settee is not something I look forward to. Dropping the screws or washers underneath the hot water system is just annoying.

Regards,

Trevor

[rene460]

Hi Andrewtas,

There is another possibility worth considering.  If you are mopping the water out, it’s not much, but because you are mopping it out, it is different water each time.  It’s coming from somewhere.

Basically, those flap valves in the pump should prevent back flow, though they probably leak a little when the pump is not operating.  There is also usually a loop up to near the deck before turning aft to the discharge point.  The loop prevents water from flowing in from the back of the boat.

Have you checked carefully for a little leak from the hot water pressure relief valve?  Or the fridge drain?  Or a few drips from the shaft seal?  Or even coolant from the engine, like the one reported in another thread.  

If it was a large leak, the pump would generally pump it mostly out unless there was a serious pump fault like a blocked flap valve or split diaphragm as suggested by others.  The automatic switch stops the pump and the water in the hose from the bilge up to the pump generally drains back to the sump unless you install a foot valve.  If you switch on the pump again, it is only the water that leaked back, not enough to fill the hose and flow overboard, it just leaks back again.  But when you mop that water out, there should be no more.  Perhaps a little more, if the water in the pump or between the pump and the high point of the loop slowly leaks back through the flap valves.  But more than that, is possibly additional water entry from somewhere.

So to me, the puzzle is, where does the extra water come from each time?  The dirty appearance suggest somewhere near the engine perhaps?

rene460

[Mistroma]

Aug 29, 2021 11:21:08 GMT rene460 said:

Hi Andrewtas,

There is another possibility worth considering.  If you are mopping the water out, it’s not much, but because you are mopping it out, it is different water each time.  It’s coming from somewhere.

Basically, those flap valves in the pump should prevent back flow, though they probably leak a little when the pump is not operating.  There is also usually a loop up to near the deck before turning aft to the discharge point.  The loop prevents water from flowing in from the back of the boat.

Have you checked carefully for a little leak from the hot water pressure relief valve?  Or the fridge drain?  Or a few drips from the shaft seal?  Or even coolant from the engine, like the one reported in another thread.  

If it was a large leak, the pump would generally pump it mostly out unless there was a serious pump fault like a blocked flap valve or split diaphragm as suggested by others.  The automatic switch stops the pump and the water in the hose from the bilge up to the pump generally drains back to the sump unless you install a foot valve.  If you switch on the pump again, it is only the water that leaked back, not enough to fill the hose and flow overboard, it just leaks back again.  But when you mop that water out, there should be no more.  Perhaps a little more, if the water in the pump or between the pump and the high point of the loop slowly leaks back through the flap valves.  But more than that, is possibly additional water entry from somewhere.

So to me, the puzzle is, where does the extra water come from each time?  The dirty appearance suggest somewhere near the engine perhaps?

rene460

I said above "I assume you mean the bilge sump and not just the bilges". It seemed to be reasonable as the original post mentioned the pump running in the "Auto" position. The float valve requires a reasonable depth in the sump before it starts the diaphragm pump and always leaves an inch or so after it drains back. The hot water tank relief valve is a common source of a small regular leak.

The sump in the 42DS has quite a high lip with a metal strainer around the top of the lip. Quite a lot of water is needed to flow over the lip and it is pretty obvious that there's water in that bilge, not just the sump. The next section aft will also be wet and probably the section behind that one as well.

I would have expected Andrewtas to mention that amount of water in the bilges. He mentions "upside down with a sponge and a bowl of dirty water" and that sounds more like reaching into the sump. Water in the sump and nowhere else would point to the hot water system. The fridge drain might be there as well but doesn't normally leak any significant amount unless ice-blocks are used for cooling.

I'd suggest checking the hose and valves for blockages as per my earlier post and also other posts.

[andrewtas]

Hello All. Many thanks for your thoughtful and considered responses.

Yes, it’s the sump that I’m referring to. A rectangular space that is reasonably deep but not too wide. The water is not so much dirty as stagnant. It’s obviously coming from somewhere, but not at a concerning level. We leave the fridge off, so shouldn’t be that. Might be the hot water. I’ll check with paper and report back.

Given that the pump turns on as soon as we hit the auto function, my guess is the most likely of the suggestions is blockage in the pipe or the pump. I’ll check them both out - and report back in the hope that it might guide others in future. 

[Mistroma]

Extremely good chance that it's the PRV if the bilges are dry and it's only a small amount in the sump. The water gets VERY hot when the engine is running and quite hot via the electric element. It is common for the pressure relief valve to pass a little water during the heating phase. If it's only a cupful then the Pressure Relief Valve (PRV) probably doesn't need to be fixed.

It is possible for the pump hose to be pulled up a bit in the sump. I seem to remember working mine down an inch or so. It might be that the float switch is actually lower than the hose end. That would account for the pump coming on and no water being pumped to the step on the stern. You can check by putting your hand into the sump and placing a finger over the pump's suction hose and asking someone to turn the pump on. You will easily feel the suction on your finger if it is working. You could also fill the sump with water and then turn the pump on to see if it drains. Of course that leaves you with a sump full of water if it isn't working as the second pump only works when water is overflowing the sump.

I keep the sump clean on our boat and do sponge it out from time to time. Only a cupful every few weeks.

[theswede]

It could also be the water level switch thats broken. 

You can test by filling the blige a litte and run the pump manually, if it pumps water the pump is ok and if you run it until water stops coming then switch to auto and the pump runs its the level switch.

[rxc]

One other item. Do you have a strainer in the suction line to the pump? It might be clogged and not allowing much water to get to the pump. Or, as someone else had said, it could be the level switch. These pumps usually leave some water behind, so the sump is never really dry.

If the water heater relief is leaking, you can "clean" it by rotating the knob on the end until it "bangs" a few times. That should help clean off some of the deposits that form on the valve seat and give you a good seal. If it still leaks, then you need to check the temperature of the water to see if it is getting too hot. The valve relieves on both presure and temperature, and the water could be too hot. That requires an adjustment of the thermostat, unless the high temperature is caused by long operation of the engine. That is more difficult to deal with, and you might just have to live with it.

[mesteve]

Is it AC condensate?

[Syrah]

When ours does what you described in your original message it is nearly always a blockage in the pipe between the diaphragm pump and the outlet at the stern step.

The hoses come out on either side of the diaphragm pump by sliding a black plastic retainer and then wiggling the fitting out.

I have been able to clear this hose in the past with a foot air pump, followed by a hose to run water through the line.

I personally have never had a blockage inside the pump (although I have pulled it apart a couple of times). Don’t undo the reddish brown retainers that hold on the valve housing while the pump is still attached to the side wall. You probably won’t get it back together without removing the pump. Doing it that way also risks dropping one of the retainers and having it disappear under the hot water tank (done that), or into the void below.

I’ve also never had a blockage in the bilge to pump line.

If the pipe is blocked and this doesn’t work to clear it, you can get access to where the hose connects through the stern by opening the panel at the back starboard side of the bed in the aft cabin (two cabin version). Remove the bead head first.

Hope this helps. Wayne

[andrewtas]

Progress report…

After some heavy (and occasionally sideways) weather in Hobart, the sump had filled and about 1cm was in the bilge. In good news, it was fresh.

No suction from the two (why are there two?) hoses when the pump is switched to auto. Took off the heads of the two intake hoses and found them to be functioning properly (open when negative pressure upstream). Traced hoses up to pump and back to outlet - no obvious problems. Inserted dinghy foot pump into intakes and applied pressure with no result (air wouldn’t flow).

Next step is to take the top off the pump and see if the diaphragm is clogged or some such…

[mesteve]

Is the second one for the manual bilge pump on deck?

[Mistroma]

Sept 5, 2021 6:42:15 GMT andrewtas said:

Progress report…

After some heavy (and occasionally sideways) weather in Hobart, the sump had filled and about 1cm was in the bilge. In good news, it was fresh.

No suction from the two (why are there two?) hoses when the pump is switched to auto. Took off the heads of the two intake hoses and found them to be functioning properly (open when negative pressure upstream). Traced hoses up to pump and back to outlet - no obvious problems. Inserted dinghy foot pump into intakes and applied pressure with no result (air wouldn’t flow).

Next step is to take the top off the pump and see if the diaphragm is clogged or some such…

Are you saying that you have had a lot of heavy rain recently? A full sump plus some fresh water in the bilge doesn't sound like the PRV, unless it has had a sudden failure and leaks a lot. Rain makes a lot more sense if you did have wet weather.

PRV makes sense if there's a small amount of water in the sump or it fills over a few weeks because the pump doesn't work.
Water might have filled the sump and flowed into the bilge. The first thing I'd do would be to check the adjacent bilges.

Water in the fore cabin bilge might be the forward tank or a deck leak (possibly the filler).
Water in the aft cabin bilge might be the aft. tank or a deck leak (possibly the filler).

Pretty obvious so far.

We had a leak in the saloon and it appeared in the bilge between galley and chart table. The bilges at the galley and bottom of the steps were always dry. Water ran forward and eventually flowed into the sump. It was certainly rain related and I discovered it was the pump out cap on port side. I removed the panel in front of the aft. holding tank and could feel water running down to the top of the tank.

It was a pain to fix because it is difficult to remove the short pipe. I undid the bolts and clamps holding the tank and raised it enough to squeeze in some sealant. I also redid to sealant between the teak deck and outer section of the cockpit coaming. That solved the leak and that's why I kept mentioning deck fillers earlier in this post.

It might be the PRV if the central bilge was wet and all the others were dry. However, water in the other bilge areas could be a clue. It could either mean a huge leak from the water tank or a leak from the deck somewhere.

We also found a leak in the aft-cabin soon after purchase. I tracked that down to missing sealant between hull and deck where the safety line gates are bolted down. Easy enough to fix with some dismantling and sealant.







Have you tried to use the manual pump in the cockpit?

[andrewtas]

Hello all - a further update.

Yes, the second inlet tube is connected to the manual pump in the cockpit (regrettably obvious - should have known that). It drained the sump easily.

The automatic pump ceased turning constantly on when the water level reduced - but then failed to come back on at all when the sump was manually refilled and the switch flicked to auto. 

So, it’s over to a marine electrician from here. He asked for a spare hatch key, so I headed to the locksmith to have one cut - and am now down the rabbit hole of finding a key blank for Jeanneau...!

[neworca1]

We replaced the mechanical float switch in the sump with an electronic sensor switch: 

www.whalepumps.com/marine/siteFiles/resources/docs/product-accessories-spares/Accessories/ElectricFieldSensors.pdf

It has no moving parts. It switches on when the water reaches an upper sensor and has a built-in shut-off delay that allows the pump to run for 30 seconds after the water level in the sump is pumped down to the lower sensor.  If the pickup hose can be placed low in the sump, the extra 30 seconds allows almost all the water to be removed before the pump shuts off.

I also mounted a pump counter in the nav station so I can tell at a glance how many times the pump has actuated...very helpful for early detection of new leaks and/or monitoring of known leaks. Both were very easy to install.

One thing I learned about the electronic sensor switch is that it can fail to shut off if "scum" is allowed to build up on its sensing surface, so it must be wiped clean every few weeks with a paper towell.

[NZL50505]

I'm in the process of overhauling my entire bilge pump setup:

1. New sump pump: to deal with the periodic accumulations that occur from minor leaks / condensation / overflows etc.:

www.whalepumps.com/marine/product.aspx?Category_ID=&Product_ID=10014&FriendlyID=Gulper-320

This is a small capacity ~19 litres / minute diaphragm pump that means it is self-priming, can deal with minor pollutants that typically clog a centrifugal pump and can pump a combination of fluids inc air / water / oil / diesel / other nasties. 

But to ensure it doesn't get clogged e.g. with hair, I'm putting a simple strum box (filter) on the front:

www.marine-deals.co.nz/livewell-pumps-bait-pumps/whale-sb4222-side-entry-strum-box

2. New bilge pump: to deal with worst case scenario of a serious leak that sump pump can't cope with:

www.marine-deals.co.nz/bilge-pumps/johnson-l4000-heavy-duty-bilge-pump?gclid=CjwKCAjw-sqKBhBjEiwAVaQ9a_DaUn-ra1TkEG8mbIpdwqVYPX0nn1gJtR0t384gvSHxxQVHKe6TdxoCURgQAvD_BwE

This is a high capacity pump 4000 GPH / ~ 300 litres per minute to help buy time to either fix a serious problem or even prepare to abandon ship.

Over the last few weeks on the water I witnessed 2 incidents in quick succession with vessels springing serious leaks and needing emergency assistance from CG / navy. It seemed like a 'message from the sea gods' and when I looked at the 'toys' that come with the standard Jeanneau bilge-pump setup I thought it deserves addressing ASAP!

 

[andrewtas]

A further - and hopefully final - update. Electrician attended and discovered that the float switch was the culprit, having given up working. With that replaced, it appears we’re good to go again.

Many thanks for your input, advice and assistance.

[andreshs1]

Sept 28, 2021 22:22:04 GMT NZL50505 said:

I'm in the process of overhauling my entire bilge pump setup:

1. New sump pump: to deal with the periodic accumulations that occur from minor leaks / condensation / overflows etc.:

www.whalepumps.com/marine/product.aspx?Category_ID=&Product_ID=10014&FriendlyID=Gulper-320

This is a small capacity ~19 litres / minute diaphragm pump that means it is self-priming, can deal with minor pollutants that typically clog a centrifugal pump and can pump a combination of fluids inc air / water / oil / diesel / other nasties. 

But to ensure it doesn't get clogged e.g. with hair, I'm putting a simple strum box (filter) on the front:

www.marine-deals.co.nz/livewell-pumps-bait-pumps/whale-sb4222-side-entry-strum-box

2. New bilge pump: to deal with worst case scenario of a serious leak that sump pump can't cope with:

www.marine-deals.co.nz/bilge-pumps/johnson-l4000-heavy-duty-bilge-pump?gclid=CjwKCAjw-sqKBhBjEiwAVaQ9a_DaUn-ra1TkEG8mbIpdwqVYPX0nn1gJtR0t384gvSHxxQVHKe6TdxoCURgQAvD_BwE

This is a high capacity pump 4000 GPH / ~ 300 litres per minute to help buy time to either fix a serious problem or even prepare to abandon ship.

Over the last few weeks on the water I witnessed 2 incidents in quick succession with vessels springing serious leaks and needing emergency assistance from CG / navy. It seemed like a 'message from the sea gods' and when I looked at the 'toys' that come with the standard Jeanneau bilge-pump setup I thought it deserves addressing ASAP!

 

Hi there

how are you connecting the 2nd bilge pump thu-hull?
I have a high-capacity pump but I am not sure where to run the water to


Cheers

[NZL50505]

Best practise says the bilge pump should exit as high as possible somewhere on the centreline - which usually means somewhere on the transom. This means you’re less vulnerable to being heeled when trying to evacuate water. And it’s another reason for needing at least one high power pump onboard that can still pump fast against a decent head of at least 1m.

And that is my plan when my mechanic has time to run the correct routing. But as a stop-gap he’s going to use one of my existing high outlets on the beam (probably one of the holding tank overflows which are just below the rubbing strake).

He’s due to start work on the new setup tomorrow (Covid delays etc).

[zofiasailing]

We’ve had 2 sources of water arriving in our sump well and around it. The fresh water in the sump itself is from the HWS overflow the salt water accumulating around the outside of the sump and passing through the bulge compartment immediately behind was eventually found to be a leak from the exhaust elbow.
The careful sponging out of above mentioned water over a period of times resulted in a spec of sponge being sucked up by the pump but it was a Goldilocks crumb- just small enough to be sucked up but just big enough to get stuck in the flapper valve. Symptom: bilge pump operating but not actually voiding.

We took the Jabsco pump out. Dismantled it. Found the spec of sponge and cleaned up the flapper and gulper diaphragm. A successful repair. Zero cost except perspiration and anxiety in a remote anchorage.

[NZL50505]

Oct 25, 2021 9:16:31 GMT zofiasailing said:

We’ve had 2 sources of water arriving in our sump well and around it. The fresh water in the sump itself is from the HWS overflow the salt water accumulating around the outside of the sump and passing through the bulge compartment immediately behind was eventually found to be a leak from the exhaust elbow.
The careful sponging out of above mentioned water over a period of times resulted in a spec of sponge being sucked up by the pump but it was a Goldilocks crumb- just small enough to be sucked up but just big enough to get stuck in the flapper valve. Symptom: bilge pump operating but not actually voiding.

We took the Jabsco pump out. Dismantled it. Found the spec of sponge and cleaned up the flapper and gulper diaphragm. A successful repair. Zero cost except perspiration and anxiety in a remote anchorage.

Which reinforces my point, namely why would you want a bilge pump that is so fragile it can disabled by a tiny piece of sponge? Imagine the mess the bilges would be after a serious water ingress event or even being layed flat for a few seconds and the debris that would get into the bilges and clog a simple pump. Hence my realisation that Jabscos supplied in many of our boats aren’t fit for purpose and should be replaced.

[andreshs1]

Oct 24, 2021 23:16:06 GMT NZL50505 said:

Best practise says the bilge pump should exit as high as possible somewhere on the centreline - which usually means somewhere on the transom. This means you’re less vulnerable to being heeled when trying to evacuate water. And it’s another reason for needing at least one high power pump onboard that can still pump fast against a decent head of at least 1m.

And that is my plan when my mechanic has time to run the correct routing. But as a stop-gap he’s going to use one of my existing high outlets on the beam (probably one of the holding tank overflows which are just below the rubbing strake).

He’s due to start work on the new setup tomorrow (Covid delays etc).

I was thinking of using the same hose as the original bilge pump, just adding a Y connector after the pump, but I guess that it would be safer to add a second hose and thru-hull...the only issue is that the port side is really busy already, so running another hose will not be easy, so I will need to look into running it on starboard

cheers