Bilge pump

[Ziffius]

So I had a call from Corfu marina telling me they had heard a pump running on my bav 39 and had gained entry to switch it off. Turns out I had left the water pump on. However, bilge was full of water and the 200L aft tank was empty. The calorifier was leaking badly. So waiting to see if I can source one locally.
In the meantime there is an inch of water throughout the bilges - not quite enough to trigger the pump from the float switch. When manually switched on it runs but doesn't seem to have enough oomph for the water to get over the syphon loop and out the boat. It's a Rule 2000. When I take the pipes off the pump seems to pump water vigorously and I've tried bypassing the one way valve that sits in the bilge but no luck. The pump has hardly been used as it's normally bone dry in the bilges.

Does the need to be a certain head of water for the pump to achieve its power - the water level is deep enough to cover the pump inlet.? Or is it just a knackered pump?

[Yngmar]

It might be an air pocket, caused by the hoses sagging between the stringers they're led through. The straightforward fix is to open the sole boards where the hose runs and simply lift the hose up a bit by hand wherever it has sagged to clear the air.

Alternatively (and possibly less work if your sole boards are screwed down like mine), you can detach the hose from the non-return valve near the pump, fill water into it from the skin-fitting end (if reachable) until the hose is full and pop the valve back on. That should also clear the air pocket and the pump will clear out the bilges pretty quick.

If it is that, in the long run you should either replace or support the sagged hose sections.

[Ziffius]

I followed the hose up into the transom. Tried undoing the hose and connecting directly to the pump, it shoots that water up the pipe but runs out of oomph by the time it reaches the up bit in the transom. Scooped and sponged the bulk of the water out for now but will try bunging up the section with the pump in the filling it with water to see if it will get it out when there is a reasonable level of water in there.

[Yngmar]

I can highly recommend having one of these on board for bilge pump experiments. Saves a lot of scooping: http://www.marinescene.co.uk/product/7557/jabsco-dinghy-bailer-hand-pump

[Symphony]

you should find the manual pump clears most of the water leaving only a small amount to be mopped up. Also worth using one of those very cheap plastic pumps with the squeeze tops going into a bucket.

[Ziffius]

I did use the manual pump for the first time, trouble was the water in the other compartments was very slow to move into the pump compartment - I kept having to wait for it. Sitting in the sun with when its nearly 40*C was a bit too much that's why I was scooping and sponging down below where it is air conditioned - well a bit as it's a portable AC unit.

[sunshine]

The electric pump on my Bavaria 30 doesn't get enough oomph until the water is at least 3 inches deep.  More than that and it really flies out of the transom, but like yours it doesn't totally empty the bilge.  How do you do oil changes?  I used the hand pump for emptying the sump to get the rest of the water out.  The little pipe fits nicely into holes in the cross sections which fill up with water and sits slightly lower than the bottom of the bilge so you get that out too.

[Lyra]

The flat bottomed bilge does create occasions when the level is not high enough for almost any pump to work properly and the only solution for the final stage is a sponge and a bucket.
I made a device for pumping water out of the bilge even if it is less than 1 cm deep.
I had a picture of it but cannot find it so hope the following description will be clear.

Purchase a brass barbed connector (something like this - http://www.harborfreight.com/14-in-barbed-fitting-68212.html)
place it in the middle of small tin can with the barbed end pointing up
melt some lead (did it in the garden on a camping stove in an old saucepan)
pour melted lead into the tin with the connector to cover the wide section of the connector leaving only the barbed section exposed.
After it cools when you take it out you have a lead disk with a hole in the middle and  barbed connector
with a file make some very shallow channels across on the bottom of the disk that lead to the hole.
purchase an outboard motor tank fuel hose (the type which has a bulb pump in the middle of it) and connect the inlet end to the lead disk - If you have some hoses you can purchase only the bulb

That's it - you place the lead disk in the bilge and use the bulb to pump the water out to a bucket. It will pump out almost everything.

[Nigel]

What stops the brass connector floating in the lead?

[Lyra]

What stops the brass connector floating in the lead?

Archimedes, I guess - the volume immersed in lead is probably not enough compared to the total weight of the piece. Although It has been several years since I made this, I do not remember that I had to support the piece or prevent it from floating.

[Lyra]

Some pictures I took yestaerday

[MarkTheBike]

This is really neat, Lyra, and I'll be making one very soon but perhaps with an angled spigot so it's easier to get into the rib voids. But - hmm - dissimilar metals in sea-water? should I fit a very tiny anode?