Ericson safety pump

[Guest]

This is mentioned in Yachting monthly in Nigel Calders article on bilge pumping (Feb02:69) and is a brilliant idea I first saw about 2 years ago. I have been trying to find on ever since but no joy - finaly found there web site but the mail was returned as undeliverable - ANYONE FOUND A SUPPLIER. If not Nigel HELP!

Roly, Voya Con Dios, Glasson, Lancaster

 

[georgeb]

They're available from West Marine (p. 503 in the 2001 catalogue) at $1200-1500. Check out their website:
www.westmarine.com

 

[Twister_Ken]

Whazzat?

Having missed any earlier reference to the Ericson pump, I've no idea what it does exactly, but thought I'd pass on the fact that Cleghorn Waring (or is it Waring Cleghorn), do a range of very nicely engineered belt driven impeller pumps - see them at http://www.cleghorn.co.uk/Products/Jabsco/bilge/bilge.html (towards the bottom of the page). They can be clutched in and out either manually or electro-magnetically

I've got drawings for them and intend to see whether I can mount one either to drive from an extended alternator drive belt, or from a pulley mounted on the prop shaft. Seems to me they may well be an excellent bilge-pump-of-last-resort (at least all the time the engine can be kept running)

Anyone done this sort of thing?

 

[simonjinks]

I wrote this up for new gear two years ago(YM Aug 2000 ish), it's a good idea as long as your engine keeps running - should be available from European Marine & Machinery Sales 01425 618704 - paul foskett was the contact

Best of Luck Simon Jinks

 

[bryantee]

Re: Whazzat?

have one on my Nova 27 .belt driven of the Flywheel on the sabb 10hp. a cam arrangement hand applies the internal clutch. ASAP Supplies have them hand or Electrical clutch.very effective, move large quantities,even use them as a deck pump with a suitable branch to a through hull.
prices between £200 to £450

<P ID="edit"><FONT SIZE=-1>Edited by bryantee on Tue Jan 29 18:34:01 2002 (server time).</FONT></P>

 

[pvb]

It\'s not what it\'s cracked up to be...

Not sure I entirely agree with Nigel Calder on the Ericson pump, Roly, (well, that’s a surprise, you’re thinking!). Calder claims that “even the smallest size has a phenomenal pumping capacity”, and indeed that’s true (but, crucially, not in a boat). The pump's theoretically rated at over 40,000 gallons an hour. But - and this is a big but - this rated capacity is at 3500rpm (pump revs). The average 30-40ft cruising yacht has a small diesel which will do maybe 3000rpm flat out, connected typically to a reduction gearbox (say 2.4:1 ratio), meaning that the prop shaft (which the Ericson pump is clamped around) is only turning at a maximum speed of around 1250rpm. At this slower speed, the output is much less, maybe only 8000 gallons an hour (the Ericson data is surprisingly a bit woolly on this).

Next problem: the Ericson pump is huge (Calder gets this right - he says “it takes up a lot of space”). The smallest Ericson pump is about 10” diameter and about 5” front to back. There’s no way it will fit in my 35ft yacht.

Next problem: before it will pump efficiently, the aperture around the prop shaft must be fully submerged. So there needs to be quite a lot of water in the boat before the Ericson will start working properly. This would affect the boat’s stability somewhat.

Next problem: it’s most likely that a dramatic leak will occur in the front part of the boat, and the Ericson is much further back. For it to work, it will be necessary to have a virtually open bilge right through the boat. With modern boat construction, stiffening ribs, etc, this is difficult to achieve.

Biggest problem: the pump only works well when the boat is flat out in forward gear. As “Motor Boat & Yachting” pointed out in its review of the Ericson pump “it is probably the case that most collisions involving breaches of the hull would damage the vessel's forward sections. In this case, driving the boat forward would tend to fill her and negate the usefulness of the pump”.

So, if you could fit one in, and if you could open up your bilges right through the boat, and if you thought that motoring flat out with a hole in the hull (and a lot of water sloshing around in the bilges) wouldn’t be a problem, then an Ericson might shift 8000 gallons an hour. And it costs about £600. Why not get 3 big 12volt bilge pumps (say 3000 gallons an hour each) instead? They’d be cheaper, they’d work as soon as water got in, they’d chuck out at least as much water, and you wouldn’t need to be motoring flat out in order for them to work.

Or buy an Etap?

 

[bedouin]

Re: It\'s not what it\'s cracked up to be...

You make some very good points - the Ericson does seem to be of very limited use.

However the rule pumps mentioned above don't seem to suffer from the same disadvantages. They seem much easier to fit and are belt driven - so they could be run from the engine without it being in gear.

 

[mikesharp]

Re: Whazzat?

We have a belt driven impeller bilge pump on our larger windfall yacht but you do need to keep a watch on the outflow because when you run out of bilge water you can guess what happens.

 

[Guest]

Ok back to origional plan

Thanks for the info, I was worried about how high the water would be before it kicked in. In a traditional narrow bilge its going to be mounted to hight to be useful. I think the point about not wanting to motor forward flat out is also pretty convincing. So its back tho the clutch pumps.

Roly, Voya Con Dios, Glasson, Lancaster

 

[bedouin]

Re: Whazzat?

Good point!

How about rigging the clutch (many are electric clutches) to a level switch - as for a conventional bilge pump (although perhaps a bit higher)?

 

[david_bagshaw]

Re:install extra pump

We installed a clutched pump on ouur previous boat.

the best way is to add ann extra pulley on the front of the crankshaft standard pulley, & drive the pump from that.

Then the standard belt drive to the alternator is not messed with or the angle of contact for the alternator pulley.

The most difficult part for us was making the mounting to hold the pump, but realy just a simple engineering task.

A really use ful device, as makes a great deck wash hose as well.

Good luck

David
www.yachtman.co.uk