Automatic Bilge Pump.......

ash · Post by **ash** » Sun Sep 21, 2008 11:00 pm

......I think that I need to invest in one. I gave myself a fright on Friday night when I found the bilges full, with the water touching the underside of the saloon sole. Mind you, at least I knew where the water had come from, and that we weren't sinking!

The Tale

The weekend previous, we didn't get up to the boat till Saturday afternoon, and I had to replace the gas cylinder, then further fiddling about with it when the cooker wouldn't burn properly - I had kinked the flexible gas pipe. At some point we found that the water tank was empty after very little use that day, we both commented that the water hadn't lasted very long, but we'd had the g.kids on board the previous w/e so blamed them and didn't think or do anything more other than refilling the tank. On Sunday, we had breky and coffee, washed dishes, more coffee and then had a very pleasant afternoon sailing with Aquaplane and Lady S as our guests, then dinner at the hotel, then coffee with Dave on board his Crabber 24. Back to the boat for a quick tidy up, and home. I had locked up when I realised that I hadn't given the bilges my usual precautionary pump out at all during the weekend. My thoughts were, " it's been fairly dry, and the new locker lids keep the boat much drier than the old, so it'll be OK"

Mistake

Fast forward to this w/e

We got to the boat in the dark on Fri night, made and had dinner. After the equivilant of about 3 kettles, the tank was dry! Something was wrong. I lifted the access board in the saloon sole and was horrified to find that the two batteries and the fuel tank were under water. It took 63 strokes of the Gusher 10 to empty the bilge. The battteries had lost some capacity, but not much,10 - 20 % and the fuel level looked the same. I drew a sample from the bottom of the tank and it seems OK. The only casualty seems to be the Lidl gas alarm which went for a swim when I accidentally knocked it off the mounting bracket.

Investigations on Sat found that the footpump for the WHB in the heads was weeping at the pedal pivot. I suspect that one of the diaphrams has gone. Will need to see if I can get spares for it, Whale Gusher Galley Pump.

Ash

cpedw · Post by **cpedw** » Mon Sep 22, 2008 11:50 am

As a point of principle, I think auto bilge pumps are a "good idea" but some experiences with them have made me a bit less certain.
The current boat (Westerly Falcon, 1986 vintage) has 2 distinct bilge areas so I thought it made sense to fit an auto electric bilge pump in each space, wired so that they are connected even when the main electric switch is off. They are on what's now called the "always on" circuit breaker, so they can be switched off if necessary. (It also keeps the radio's memory powered so that it gives instant radio 4.)
The first problem arose during our summer cruise about 2 years after we got the boat. Comfortably and peacefully anchored in Loch Moidart, there was a persistently recurrent buzzing noise. I put it down to external factors at first, but after half an hour it was getting annoying so I eventually tracked down a bilge with some (not a lot of) water in. The float switch was switching on the bilge pump, pushing water into the pipework which includes a swan neck, lowering the level in the bilge, switching off the pump, allowing the same volume of water (nothing had got over the swan neck) back into the bilge, switching on the float switch again which met the barrel of bricks descending ....
To speed up noticing the active pump in future, I have fitted a 12V led in parallel with the pump but switched by the float switch, in a prominent place so we'll know straightaway what's causing the problem, even if we can't hear the pump. (I took the chance to install warining lights for concealed lights that get switched on and forgotten - there's one in the cockpit locker and one in the engine bay.)
I chose Mayfair 508443 cheap switch and pump. The pump bottom bearing gets sticky after a time, seizing the motor. The float switch on one failed too. But fortunately, you can replace bits and I'm so mean I haven't taken these out and replaced them with something decent.
I still think it's a good idea, but I really ought to get better quality pumps and switches; to fulfil their main function these need to be very reliable.
Derek

SteveN · Post by **SteveN** » Mon Sep 22, 2008 8:36 pm

I can thoroughly recommend the Rule ECO air-operated switches:
http://www.mediades.co.uk/products/RULE ... WITCH.html

Fitted one several years ago and it just keeps on working! (Never yet in anger, but every time I test it with a jug full of water).

The electrical part is mounted high above the bilge level with just the air tube and it's end fitting descending into the bilge. The sensitivity, i.e. the 'on' water level, can be adjusted with a small allen screw on the front of the unit.

You don't see them about much, but they're worth tracking down.

aquaplane · Post by **aquaplane** » Mon Sep 22, 2008 9:10 pm

It sounds like the sort of switch used in a washing machine. Someone with a bit of electrickery nouse may be able to nick one off a scrap washer. Or isn't it worth it if the one you mentioned is cheap as chips?

ash · Post by **ash** » Mon Sep 22, 2008 10:22 pm

Thanks guys

I'm sure that I kept an air pressure switch from the last washing machine. From memory there a number a connections, which would represent the different water levels. I'm not sure if any are adjustable. I'm also not sure if they would stand up to DC currents. (AC currents are easy to stop because the voltage cycles through zero volts - DC currents need a bigger airgap to kill off the arc)

I already have a small electric bilge pump, stored in a locker, and fitted with long lead, crocodile clips, and hose for undefined purposes (which I've yet to discover)

The pumps are fairly cheap, it's the switch which seems relatively expensive for something reliable.

I could install a pump and switch fairly easily on the top of the lower part of the fuel tank, and although this would prevent a re-occurance of the tank and batteries being flooded, would leave a lot of water in the bilge.

The only other access to the bilge is here

so is a bit limiting.

I fancy one of these

Supersub 500

which hopefully I could attach to a 'stick' to enable me to poke it past the pipes into the bilge. I would also need a remote style of switch, either the air pressure type or the solid state ones with probes.

Do the solid state probe type work with fresh water?

I think that I would tend towards the air pressure type as it would be easy to attach the pipe to the same 'stick'.

Ash

aquaplane · Post by **aquaplane** » Mon Sep 22, 2008 10:33 pm

The difference between sea and Loch Lomond water is mainly in the density. There will be enough impurities in Loch Lomond water for it to conduct, it's not distilled water, especially when it's been in a bilge, so it would act like a mercury switch.

I don't know what the density of sea water is, but I bet it's as near 1 as makes sod all difference, unless your name is Plimsole.

Bejasus · Post by **Bejasus** » Wed Sep 24, 2008 4:29 pm

I replaced a Jabsco belt driven diaphragm pump and float switch, with 2 of these. http://www.jabscoshop.com/item.asp?ls=R ... B8&id=1122.
They turn on every 2 minutes ish for a second. If they sense water, then they pump until it's gone, and then go back to the previous mode. I put one on either side of the bilge and teed them together with a check valve in each line to prevent one pumping through the other. This also stopped any flow reversal. Battery power used in this way is minimal.

Clyde_Wanderer · Post by **Clyde_Wanderer** » Wed Sep 24, 2008 7:23 pm

I have a rule pump in the lowest part of the bilge, but had some promlems with the rule float switch which would either stick on or not make when needed, so dumped it and bought an Eco switch which has a little cup that sits at a predetermend position in the bilge and has a rubber tube that connects to the actual diaphram switch located under the chart table well away from any source of water.
When the water level risses and fill the little cup to a certain level it pushes the air up along the tube distorting the diaphram and operating the switch.
I find it a lot more reliable and consistant than the rule switches, plus you can cheat and use it to switch two pumps, on auto, though not both at the same time.
The Lavac type heads with the Henderson pumps can also be used to pump out large quantities of sea in an emergency.

ash · Post by **ash** » Wed Sep 24, 2008 9:00 pm

Clyde_Wanderer wrote: an Eco switch which has a little cup that sits at a predetermend position in the bilge and has a rubber tube that connects to the actual diaphram switch located under the chart table well away from any source of water.
When the water level risses and fill the little cup to a certain level it pushes the air up along the tube distorting the diaphram and operating the switch.

Your description sounds like the link posted by SteveN

Rule Eco Switch

I think that this is the one which would suit me best. Seems to be available from a few on line shops.

Ta

Ash

Clyde_Wanderer · Post by **Clyde_Wanderer** » Wed Sep 24, 2008 10:10 pm

ash wrote:
Clyde_Wanderer wrote: an Eco switch which has a little cup that sits at a predetermend position in the bilge and has a rubber tube that connects to the actual diaphram switch located under the chart table well away from any source of water.
When the water level risses and fill the little cup to a certain level it pushes the air up along the tube distorting the diaphram and operating the switch.
Your description sounds like the link posted by SteveN

Rule Eco Switch

I think that this is the one which would suit me best. Seems to be available from a few on line shops.

Ta
Yes ash but it obviousley took me longer to type than him, as his reply wasent there when I started to type.
I got my ECO at Duncan's Chandlers.

Ash

ash · Post by **ash** » Wed Sep 24, 2008 10:45 pm

C_W

Thanks for info.

The ECO isn't on Duncan's website.

I like to use them if I can. By the time that you add on delivery to the onlines, Duncans are usually fairly competitive, and it's always good to feel something in your hands before you buy.

Ash

sahona · Post by **sahona** » Thu Sep 25, 2008 10:01 am

don't know the price of an eco switch, but the afore-mentioned washing machine switch will do the job. you could pay for a "spare part" or rob one from a scap w.m. or dishwasher. I use it to pick an automobile courtesy light delay relay, which controlls the pump. This stops it cycling, as the pump runs for a few seconds after the water level has dropped below the switch sensor. The main thing is that all the electrics are well away from the water, the relay being physically between the battery and pump keeping the thick wire to a minimum.(all the rest is thin cheaper stuff) .

Clyde_Wanderer · Post by **Clyde_Wanderer** » Thu Sep 25, 2008 6:32 pm

[quote="ash"]C_W

Thanks for info.

The ECO isn't on Duncan's website.

I like to use them if I can. By the time that you add on delivery to the onlines, Duncans are usually fairly competitive, and it's always good to feel something in your hands before you buy.

Ash[/quote
ash I always deal with Duncans, and find them very helpful especially wee Ian who always gives a good deal. I cant be bothered with buying stuff of the net.
Why dont you phone them and ask if they have one in stock. 0141 429 6044
Cheers, C_W