Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 05-08-2012, 12:53   #1
Registered User

Join Date: Oct 2011
Location: Portland, OR
Boat: Ericson 38
Posts: 12
submersible vs non-submersible bilge pump

I need to replace the bilge pump on my '84 Ericson 38. Currently it's a non-submersible pump mounted just below the sink in the galley. I don't seem to see much in the way of new non-submersible pumps on the market or even articles discussing/reviewing non-submersible pumps.

Is there a reason these non-submersible pumps seem to be less popular? Should I stick with a non-submersible since its whats already there, or in the interest of having an easy to find replacement in the future would a submersible pump be a better choice?

If I do end up sticking with a non-submersible are can anyone direct me to some reviews/favorite models?

Thanks,

Matt.
__________________

__________________
assfortress is offline   Reply With Quote
Old 05-08-2012, 12:59   #2
Moderator Emeritus
 
David M's Avatar

Cruisers Forum Supporter

Join Date: Sep 2007
Location: San Francisco Bay
Boat: research vessel
Posts: 10,150
Re: submersible vs non-submersible bilge pump

Submersible pumps are typically centrifugal pumps, which use spinning vanes, similar to the compressor blades of a jet engine, as the impeller. This is a very quick way of ridding water from your bilge. The downside to centrifugal pumps is that the vanes must be submerged for them to work.

Non-submersible are displacement pumps because they can "gulp" either air or water. In other words they can grab individual units of air or water...similar to a piston engine that has a chamber an inlet valve and and outlet valve, or something similar. Non-submersible pumps, for the same horsepower are slower. They also tend to be more expensive because of their complexity.

If you have a place in the very bottom of your bilge where all the water collects and there is room for a centrifugal pump, then I would go that route. If there is no room where the water collects, then go with a displacement pump. Remember to put a strainer at the end of the hose.

Some people have both where the vane pump is not normally used except for emergencies. If you start taking on a large amount of water, the centrifugal pump will have a better chance of keeping up with the flooding, where you placed it at the lowest point in the bilge that you could fit it. The displacement pump would be used for removing that last little bit of annoying water in the bilge.
__________________

__________________
David

Life begins where land ends.
David M is offline   Reply With Quote
Old 05-08-2012, 14:13   #3
Registered User
 
xymotic's Avatar

Join Date: Dec 2007
Posts: 1,076
Re: submersible vs non-submersible bilge pump

the reason they are not 'popular' is that they are vastly more expensive.

Also: "Assfortress" :? lmfao
__________________
xymotic is offline   Reply With Quote
Old 05-08-2012, 14:16   #4
Registered User

Join Date: Oct 2011
Location: Portland, OR
Boat: Ericson 38
Posts: 12
Re: submersible vs non-submersible bilge pump

I'd be interested in reading some reviews of whats out there... all I've come across (in places like Practical Sailor) are comparisons of the submersible models. Any links would be greatly appreciated!

xymotic: why do you prefer them?
__________________
assfortress is offline   Reply With Quote
Old 05-08-2012, 14:32   #5
Moderator Emeritus
 
David M's Avatar

Cruisers Forum Supporter

Join Date: Sep 2007
Location: San Francisco Bay
Boat: research vessel
Posts: 10,150
Re: submersible vs non-submersible bilge pump

I think the more popular brands of the vane pumps are pretty much the same, Attwood, Rule and Shure. No bilge pump in my experience will last a long time and I have gone through a lot of bilge pumps. The seals eventually leak destroying the motor.

You want a pump that is going to be able to kick butt when needed, which if it comes down to one type or the other I would pick a vane pump. Displacement pumps are good for scouring but not so good for removing water at a high rate.

Also, don't trust the rating (GPH rate). All the rating means is no pressure head on the pump. Meaning there is no water being pumped up hill or through any hose for that matter.
__________________
David

Life begins where land ends.
David M is offline   Reply With Quote
Old 05-08-2012, 15:32   #6
Senior Cruiser
 
Blue Stocking's Avatar

Cruisers Forum Supporter

Join Date: Dec 2008
Location: St. Georges, Bda
Boat: Rhodes Reliant 41ft
Posts: 4,114
Re: submersible vs non-submersible bilge pump

Put 3 ft of water in your bilge, stick your head thru the floor hatch, and try to service the submersible while imagining the boat is taking on water.

Now service the attached strainer on the belt driven pump, which is closer to sitting eye level, while you work comfortably on the salon floor.

IMO, stick with the belt driven.
As to cost, my ITT jabscos are 14 yrs old, in the same period, I know boats which have had submersible replaced 3 times.
Jus sayin.
__________________
so many projects--so little time !!
Blue Stocking is offline   Reply With Quote
Old 05-08-2012, 15:34   #7
Registered User

Join Date: May 2012
Posts: 466
Re: submersible vs non-submersible bilge pump

The bilge in my Ericson38 was such that installing a large high capacity pump would not work very well the pump had to go in one part of the grid area and the float in another which caused the pump to drain one while the others still had water in them running pump dry I was never happy with either pump set up(centrifugal or vane) the hose under the grid to the bilge was to small and would require wrecking the sole to access to change only to have problem mentioned above so I had to be satisfied with small capacity pump
I made sure my manual pump was flushed often and in good working order and always remembered this saying " There is no better bilge pump than a scared man with a bucket"
Make sure you get spare parts for vane type it will burn up vanes at some point or wear out Note I ended with a centrifugal pump with relay to help speed of pump also!
__________________
sartorst is offline   Reply With Quote
Old 05-08-2012, 15:47   #8
Moderator Emeritus
 
David M's Avatar

Cruisers Forum Supporter

Join Date: Sep 2007
Location: San Francisco Bay
Boat: research vessel
Posts: 10,150
Re: submersible vs non-submersible bilge pump

A Rule 2000 is going to be faster and have more endurance than a bucket brigade out the companionway.

There are fully automatic bilge pumps in case float switches are a problem.
__________________
David

Life begins where land ends.
David M is offline   Reply With Quote
Old 05-08-2012, 15:53   #9
cat herder, extreme blacksheep
 
zeehag's Avatar

Cruisers Forum Supporter

Join Date: Jul 2008
Location: furycame alley , tropics, mexico for now
Boat: 1976 FORMOSA yankee clipper 41
Posts: 17,769
Images: 56
Send a message via Yahoo to zeehag Send a message via Skype™ to zeehag
Re: submersible vs non-submersible bilge pump

my 35mII has 2 pumps--one hiding in a place necessary for emergency use--2200gph with flapper switch--and one fully automatic 1100 gph under sole near the water filter for engine. the rule fully automatic pump works great and does the job-- when needed, the other--i think is abaft the engine--kicks in and pumps boat dry.
what ever you have, make sure you do not have to work on it when the chips are down--you WILL sink.... check em and rewire them if needed before you go out on a passage. check the float switch and have a spare or 2, and make sure primary is good --you can never have enough pumps or line.
a non submersible may be just the ticket for emergency, tertiary, use.
zeehag is offline   Reply With Quote
Old 05-08-2012, 16:30   #10
Moderator Emeritus
 
GordMay's Avatar

Join Date: Mar 2003
Location: Thunder Bay, Ontario - 48-29N x 89-20W
Boat: (Cruiser Living On Dirt)
Posts: 31,579
Images: 240
Re: submersible vs non-submersible bilge pump

I recommend 3 Pumps.
An electric Primary diaphragm, Secondary electric centrifugal, and a manual Tertiary* diaphragm pump.

Where two electric pumps are installed**, the smaller capacity non-submersible diaphragm pump is usually tasked for primary use, pumping small amounts of normal ingress (mast drainage, packing gland lubrication & etc); whilst a larger capacity submersible vane type centrifugal pump is tasked with emergency (tertiary*) tasks.

*Tertiary usually relates to a “third order” (behind primary & secondary), though is often misused to describe “final”.

** See also ➥ http://www.docksidereports.com/bilge_water_blues.htm
__________________
Gord May
"If you didn't have the time or money to do it right in the first place, when will you get the time/$ to fix it?"



GordMay is offline   Reply With Quote
Old 05-08-2012, 17:21   #11
Registered User

Join Date: Nov 2011
Location: Montegut LA.
Boat: Now we need to get her to Louisiana !! she's ours
Posts: 3,421
Re: submersible vs non-submersible bilge pump

Ive used all 3 types, and the one I know I can depend on is my manual hand pump !! I ck it everyday! and will even put water in the bilge to make sure it and my other pumps work !! Our Colvin was so dry we never knew if our pumps worked or not ! So we cked them at least once a week by tripping the float switchs, and such ! just our 2 cents
__________________
Bob and Connie
bobconnie is offline   Reply With Quote
Old 05-08-2012, 19:07   #12
Registered User
 
xymotic's Avatar

Join Date: Dec 2007
Posts: 1,076
Re: submersible vs non-submersible bilge pump

Quote:
Originally Posted by Blue Stocking View Post
Put 3 ft of water in your bilge, stick your head thru the floor hatch, and try to service the submersible while imagining the boat is taking on water.

Now service the attached strainer on the belt driven pump, which is closer to sitting eye level, while you work comfortably on the salon floor.

IMO, stick with the belt driven.
As to cost, my ITT jabscos are 14 yrs old, in the same period, I know boats which have had submersible replaced 3 times.
Jus sayin.
^^^^^ That's why

Also, after 14 years, you can fix it the others are pretty much disposable.
__________________
xymotic is offline   Reply With Quote
Old 05-08-2012, 19:35   #13
Registered User

Join Date: May 2012
Posts: 466
Re: submersible vs non-submersible bilge pump

ON an Ericson 38 you dont have most of these options due to grid system!
__________________
sartorst is offline   Reply With Quote
Old 05-08-2012, 19:59   #14
Registered User

Join Date: Feb 2012
Posts: 2,441
Re: submersible vs non-submersible bilge pump

Quote:
Originally Posted by sartorst View Post
ON an Ericson 38 you dont have most of these options due to grid system!
Once water starts entering the hull in quantities a high capacity pump is there to handle, the grid partitions will quickly be underwater. Seems to me you need a high capacity pump (several, if going offshore) regardless of the details of how your bilge is configured.

If need be, surely you can have a plug-in, 'wandering' suction hose to enable the same pump to evacuate individual compartments, once you have stemmed the inflow.
__________________
Andrew Troup is offline   Reply With Quote
Old 05-08-2012, 20:21   #15
Registered User
 
Caribsailors's Avatar

Join Date: Jun 2008
Location: Somewhere in the Caribbean
Boat: Beneteau First 38
Posts: 308
Images: 23
Re: submersible vs non-submersible bilge pump

Quote:
Originally Posted by GordMay View Post
I recommend 3 Pumps.
An electric Primary diaphragm, Secondary electric centrifugal, and a manual Tertiary* diaphragm pump.

Where two electric pumps are installed**, the smaller capacity non-submersible diaphragm pump is usually tasked for primary use, pumping small amounts of normal ingress (mast drainage, packing gland lubrication & etc); whilst a larger capacity submersible vane type centrifugal pump is tasked with emergency (tertiary*) tasks.

*Tertiary usually relates to a “third order” (behind primary & secondary), though is often misused to describe “final”.

** See also ➥ Bilge Water Blues: Boat Maintenance/Repairs
I recommend one more...... a centrifugal that you can place anywhere in the boat. When you are healed and taking on water from somewhere, it may not always get to your bilge pump.

Cheers
__________________

__________________
As I sit, a swirling sea of passion gives it's poems in waves underneath me.
The whispers of the sun in my eyes, a silence within.
Rhythm of the surf, drums of the sea. Thoughts tumble and toss about the deep blue abyss inside me, where the love of you dwells.
I'm fighting currents to get back to you, listening to the flow of your liquid language as you beckon me, "Come Play"
Mariners Cove, CI. Anonymous.
Caribsailors is offline   Reply With Quote
Reply

Tags
bilge, bilge pump

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off




Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 08:57.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.