Need another bilge pump?

E

eddystone

Well-Known Member
Joined
18 Aug 2013
Messages
1,936
Location
North West Devon
Visit site
My new (to me obviously) Sadler 32 has a single manual bilge pump. I guess Sadler in 1986 thought that was OK and that was what my last boat had (although much smaller). I was thinking of getting an additional one, manual or electric, fitted.

Do you think this is an essential? I wonder about automatic electric bilge pumps. I seem to remember something nasty could happen with an electric bilge pump sustained by a trickle charge on a mooring but I can't remember what.

My own thoughts were whether an electric switch in the bilge could cause a spark - maybe not such a good idea if there was any trace of gas? And couldn't it short out if the saloon was flooded?
 
Very common to have a submersible electric pump as well as a manual one. Choice of having it automatic or manual, but modern boats tend not to leak so automatic probably not necessary. Just replaced a 12 year old electric in my boat as it had seized through lack of use - that is never been used in anger.
 
Flappy style float switches are prone to creating DC earth current leakage and this can cause zinc wastage - I found this happening on my boat earlier this year. I replaced the duff switch with a solid state one, which is totally sealed. Problem solved. It also allows a pump overrun so the pump doesn't sit there cutting in and out as the boat naturally rolls a few degrees.
 
You definitely need a second bilge pump and preferably an electric one. Get a big 1 so that in an emergency the pump can do the pumping while you try and staunch the leak.
 
If you think you need an electric pump then install a separate pump & a switch like the waterwitch. combined pumps with a float are useless, water always gets in via the cable entry.
for the past 16 years i have had a waterwitch & a remote PAR diaphragm pump in the lazerette, no cables are ever in water.
 
You might like to look at my solution for a Sadler 34 http://coxengineering.sharepoint.com/Pages/bilgepump.aspx This was built to overcome the same situation that you face - the only pump on a 34 is sited in the engine bilge that is totally isolated from the rest of the boat. I have never found the need for any automatic bilge pump on this boat, it should be perfectly dry.

So far as an automatic bilge pump is concerned there is never going to be a spark. I have one on my other boat, with an automatic switch with no moving parts, triggered by water bridging two electrodes. It seems to work perfectly.
 
vyv_cox said:
You might like to look at my solution for a Sadler 34 http://coxengineering.sharepoint.com/Pages/bilgepump.aspx This was built to overcome the same situation that you face - the only pump on a 34 is sited in the engine bilge that is totally isolated from the rest of the boat. I have never found the need for any automatic bilge pump on this boat, it should be perfectly dry.

So far as an automatic bilge pump is concerned there is never going to be a spark. I have one on my other boat, with an automatic switch with no moving parts, triggered by water bridging two electrodes. It seems to work perfectly.
Click to expand...

thanks

that sounds like a good solution - presumable you could just have a longer hose going over the side instead of into the cockpit. I'll go and look at the logistics of this with the smaller 32.
 
I would recommend having an automatic - modern boats may not leak from below, but they can 'leak' from above. Ours nearly sank in the harbour a few years ago in a strong easterly blow which caused waves to lap over the transom - each lap was almost negligible, but the cumulative effect over the whole night resulted in a foot of water throughout in the morning. Luckily it wasn't enough to sink it, but much more and it would probably have done. I have since fitted a Rule Mate 1100 gph (e.g. http://www.ebay.co.uk/itm/NEW-RULEM...-Pumping-/151074732105?_trksid=p2054897.l4276) which is both manual and automatic, and which keeps it as dry as a bone despite several blows as big or bigger since then.
 
ghostlymoron said:
You definitely need a second bilge pump and preferably an electric one. Get a big 1 so that in an emergency the pump can do the pumping while you try and staunch the leak.
Click to expand...
In practice most electric bilge pumps will be useless if you have a serious leak. In theory they are XXX gallons per hour, but by the time they are pushing water up and out out through longish pipe runs the actual flow rate is much, much lower.

I have been in two near-sinking incidents in about 45 years sailing, one on an ancient wooden gaff ketch that had (we later realised why) two huge manual pumps, the other on a wooden Chinese junk, where the electric bilge pump totally failed to cope with a leak. No working manual pump, so it was buckets.
 
jwilson said:
In practice most electric bilge pumps will be useless if you have a serious leak. In theory they are XXX gallons per hour, but by the time they are pushing water up and out out through longish pipe runs the actual flow rate is much, much lower.
Click to expand...

Agreed, it will be lower, but I have measured ours and it does around 900 gph with an 80 cm riser to the outlet, so that isn't too bad. The big problem though would be if you are swamped and the electrics cut out. But for getting rid of any gradual build up of rainwater or seawater when the boat is unattended, I think they are great.
 
Last edited:
OK so I can see an advantage to an automatic electric pump - you can leave it to do it's stuff while you look for/plug the leak - when you've done that you can leave it on and get onto the manual pump, doubling up the pumping capacity. I like the idea of leaving it on auto mode when the boat is unattended, except it's probably going to drain the battery eventually (boat could be unattended for months). I thought I read somewhere when that happens water could siphon back in or is that not possible?
 
The older ones did switch on and off every so often to determine if water was present by the mechanical resistance to the impellor, but the newer ones work by electrical resistance across two electrodes, and only consume power when pumping. I guess it could flatten the battery if there was too much pumping, but the solution then is a solar panel to charge the battery in between times. That's one of my winter projects.

Never had any water siphon back in as the outlet is just below the gunwale. If the water ever got that high, siphoning probably wouldn't be your major worry. There is a small amount of water in the riser tube which drains back, but this is fairly negligible.
 
Last edited:
rbmatthews said:
Agreed, it will be lower, but I have measured ours and it does around 900 gph with an 80 cm riser to the outlet, so that isn't too bad. The big problem though would be if you are swamped and the electrics cut out. But for getting rid of any gradual build up of rainwater or seawater when the boat is unattended, I think they are great.
Click to expand...

They are great for that in a RIB, but with a grp or steel yacht, you really ought to concentrate on keeping the water out in the first place. Also be very wary of the possibility of pumping out oily bilge water. People are getting very sensitive to that.

RORC rules used to require 2 manual bilge pumps, one operable from below decks and one from on deck.
I see some sense in that.
One thing I think is quite a good idea is a centrifugal pump mounted on a rigid length of pipe. It's useful for washing the decks and would double as an extra bilge pump in a crisis
 
eddystone said:
My new (to me obviously) Sadler 32 has a single manual bilge pump. I guess Sadler in 1986 thought that was OK and that was what my last boat had (although much smaller). I was thinking of getting an additional one, manual or electric, fitted. Do you think this is an essential?
Click to expand...

Well, when we first had ours the surveyor thought so and the insurance company (and I) agreed with him, so the single manual was augmented with an automatic in the engine bilge. On a related matter, I also wondered at one time about fitting a valved Y diverter into the engine's sea water intake so that in emergency it could draw from the bilge (an arrangement found on some motor boats, I think). Someone pointed out that the flow rate with a small auxiliary would be limited, but "ev'ry little 'elps" we are told ... and it would keep going as long as the engine did! Anyone else thought of that, or done it?
 
prv said:
You never dip the lee rail under when going to windward in a breeze?

Pete
Click to expand...
Frequently - sea water tends to flow back in to the shower sump if I push her too hard over - easy fix - switch on the shower sump pump, aka auxiliary bilge pump.
 
Hydrozoan said:
Well, when we first had ours the surveyor thought so and the insurance company (and I) agreed with him, so the single manual was augmented with an automatic in the engine bilge. On a related matter, I also wondered at one time about fitting a valved Y diverter into the engine's sea water intake so that in emergency it could draw from the bilge (an arrangement found on some motor boats, I think). Someone pointed out that the flow rate with a small auxiliary would be limited, but "ev'ry little 'elps" we are told ... and it would keep going as long as the engine did! Anyone else thought of that, or done it?
Click to expand...
Y-valve on engine intake not uncommon, and my engine at least - Yanmar 27 hp - chucks water out the exhaust at a greater rate than the Jabsco electric bilge pump does by the time it's raised 5 ft and run along 20+ ft of pipe to near the transom. The Y-valve thing is OK if you are very confident everyone who might use the boat knows about it....
 
You must log in or register to reply here.

Share this page

Top