Conference unifix::sailing

    Most Bilge pumps do not require primimg. In fact even if the boat
    is dry I always pump a little to rid the boat of any potential nasties
    ie gas (As in cooking not petrol) leaks etc. The strum box is located
    in the lowest part of the bilges........ Last summer I had a small
    gas leak and it kept me from blowing up until I had it fixed......
    One of the most popular makes fitted to production boats in the
    UK is Whale I am not sure of the rating .....
    
    Pete
    

    Where did you find a 2000 gallon per minute pump, and where are
    you going to find a place for it and the engine it takes to run
    it?   :)
    
    You really meant 2000 gallon per hour?   What type/brand are you
    thinking of?  They each have different characteristics and needs
    which would be easier to relate if we knew what models you are thinking
    about.
    
    Walt 

    Walt,
    
     RIGHT! Sorry, major typing error! My brain needs rebooting this
    morning.
    
     2000 gph. I was thinking the RULE brand of pumps. I have heard
    one pro vote, and one con vote. Strangely enough, both votes dealt
    with the unit's reliability - how long they will last!
    
     I would appreciate any experiences, or suggestions.
    
    			Thanks,
    
    			Gregg

    I had a smaller Rule in my last boat (1200GPH I think, a 25' sloop).
    
    It never gave me any reliability problems.
    
    The advantages of this rigid impeller type pump seems to be that 
    it can run dry without causing any problems, and it self primes.  
    They seem to work best when just put at the bottom of the bilge. 
    They usually provide their own strainer and can pump lots of small 
    objects right thru. If they do clog they are very easy to pull 
    apart to unclog (at least they used to be).
    
    The disadvantages are that it cannot pump much of a head without
    a major reduction in thruput, and they back siphon real well when
    not running, so you will need an antisiphon loop.
    
    
    The PAR (ITT/Jabsco) diaphram pumps cannot be imersed in the bilge, 
    but they also self prime. They also do not back siphon and can pump
    quite a head.   These should be used with an inline raw water strainer,
    because tearing down the pump to remove a chunk of debris hanging
    a diaphram open or blocking a port is not a fast job.

    I do not recommend the rubber impeller type pumps like
    Wilcox-Crittenden puts out. They cannot be run dry without overheating
    the impeller and scoring the chamber. They also take a while to
    prime and cannot be immersed.
    
    Walt

    re: .4
    
     Thanks Walt - that was just the type of info I was looking for.
    
    When you say that the Rule's throughput drops off if it is pumping
    much of a head, what height are you talking? I would estimate that
    the height from the bottom of my bilge to the transom thru-hull
    to be 2 feet max. What kind of a reduction should I expect?
    
     Right now, based on your info, I am leaning toawrds the Jabsco.
    The rule is self straining, and can be submerged, but the Jabsco's
    plusses are the no reduction in throughput.
    
    
    				Thanks,
    
    				Gregg

    Re. "no reduction in throughput".  Even pump will have reduced pumping
    capacity as long as the output pressure is fixed! No vender can
    overcome the laws of nature.....the greater the head the less the
    capacity until you reach a point head pressure equals pump pressure
    and the capacity reaches zero. 
    
    There is the possibility that some pump cannot maintain output pressure
    steady as head pressure increases. This may occur in centrifugal
    type pump and is less likely in "direct" type pumps such as a diaphram
    with check valves.
    
    Jerry
     

The Rule centrifugal pump:

  is much easier to clean if it clogs (cleaning the Jabsco is a difficult 
  and time consuming process)

  has much greater capacity (both gallons pumped per hour and gallons pumped 
  per hour per dollar)

  uses more electrical current (for larger pumps)

The Jabsco pump:

  is more reliable (maybe, but it does clog easily)

  will pump the bilge almost dry

Our Jabsco has a capacity of only 330 gallons per hour ($181.50 list) 
while our Rule has a capacity of 3500 gallons per hour ($124 list). The
Jabsco keeps the bilge dry, while the Rule is mounted well above the
bottom of the bilge (so we can get at it easily) and is intended for
major emergencies only. I would suggest, in general, the highest
capacity pump you can afford and that will fit in your bilge. The rated
capacity of most if not all pumps is the capacity with no hose attached
to the outlet. Large hoses will allow pumping significantly more water
than small hoses. I'd suggest 1.5" diameter minimum. 

A thought I might have thought before: Small boats are more likely to 
take water aboard from waves or wakes than large boats (due to their 
lower freeboard). Also, fewer gallons of water are needed to sink a 
small boat than a large boat. This implies that small boats need big 
pumps. Also, be sure you have a manual pump with reasonable capacity in 
case your electrical system fails.

Alan

    .6 is correct that increasing the head should cause a decrease in
    pump output, regardless of pump design.  This is true, however
    the diaphram type put out by Jabsco decreases much less rapidly
    than impeller types like the Rule for identical increases in head.
    
    
    2 feet of lift is not much, so I dont think you will see much loss
    in capacity with the Rule and following Alans suggestion of a large
    hose.  I seem to recall Practical Sailor did a comparative test
    of automatic pumps once where the effect of head and outlet hose
    size really showed up.

    Walt

    Thanks for all the good info.
    
     I was wondering if anybody has rigged a "manifold" on the intake
    of a Jabsco-like pump, so that, when the boat is heeled over, the
    pump can still clear the bilge? The intake would run athwartships,
    and be connected to the pump by means of a T connector. In this
    manner, no matter what the angle of heel SOME of the intake holes
    will be under water - some won't.
    
     What is the effect of sucking in air through the intake along with
    water? I would think that the total throughput would be decreased.
    Some friends of mine have installed 2 smaller pumps, one port and
    one starboard, to pump water when heeled.
    
     The manifold is a way out idea, but I like to explore way out ideas!
    
    			Thanks,
    			
    			Gregg

>     I was wondering if anybody has rigged a "manifold" on the intake
>    of a Jabsco-like pump, so that, when the boat is heeled over, the
>    pump can still clear the bilge? The intake would run athwartships,
>    and be connected to the pump by means of a T connector. In this
>    manner, no matter what the angle of heel SOME of the intake holes
>    will be under water - some won't.

Pumps prefer to suck air in such a situation.

--RS

    Right - I had that shown to me soon after I entered the note!
    
    		Gregg

    Don't give up totally. You could overcome the sucking air problem
    with a simple flapper valve. If a valve is installed at the "tee"
    such that when you are heeled, the higher end of the manifold is
    closed, then it might works fine. This has teh advantage of allowing
    you to have a single very high capacity pump without doubling the
    cost. It also has the disadvanage of possible mechnical failure.
    
                              |    |
                              |    |  <--- pump line
                              |    |
     low side -->  -----------    /----------------  <-- high side
                                 /
                   -----------  || ----------------
                                ||
                     
    
    			 	^
    				|
    			counter balance weight
    
    Lousy diagram, but you get the idea. The swing angle of the weight
    would be small to insure that the weight would toggle for small
    heel angles.
    
    Always engineering....
    Jerry
     

    Has someone actually produced a valve such as described in .12 ?
    
    Walt

    I'm not aware of a commercial unit, but did see a "home brew" several
    years back. It was a bit leaky, but I always thought that with a
    little extra care when fabricating the valve parts, would produce
    a very useful device. Perhaps some of the mechanics out there can
    help.
    
    Jerry
    

There are at least three simpler solutions to the problem:

1. Fix the leaks in your present boat.

2. Buy a boat that doesn't leak.

3. Buy a boat with deep bilges.

:-)

    re: .15
    
    In response to your "simpler" solution:
    
    1) the boat doesn't leak 
    	- it is a racing boat, 
    	- a "wet" boat (low freeboard), 
    	- can be and IS put on the rail, and, 
    	- via limber holes, any water that enters the cockpit can,
    and should, work its way to the lowest point in the bilge, where
    the pump is. 
    
    			Gregg

    Re .9
    
    Simpler yet, leave a long intake hose on the pump which can be put
    to the lower side when heeled.  Mount the pump centrally and work
    the pump with strings attached to the handle.  Works well on my
    open cockpit racing sailboat.
    
    - gene

    Anyone have any experience with Atwood pumps? 
    
    I just got an Atwood 500gph model. I picked the Atwood over Rule
    because tha Atwood can be run dry and the Rule small models cannot.
    
    Ed 

    Anybody have any ideas on what type of Bilge pump should be used for
    emergency situations? Currently, I have a ITT/Jabsco as my main
    Electrical pump with a 10" whale gusher manual pump mounted down below.
    I've read in various literature that a manual pump should be mounted
    where the helmsman can pump while on station. This would give the pump
    a 6' lift. It would mount within the engine compartment which is below
    the cockpit.
    
    Any ideas? Also, would it be prudent to rig an engine driven pump in
    addition to the above or in place of the above?
    
    Robert 

re .19: 

Read, if you haven't already, Note 738. There are obviously situations 
with which no pump can cope, but the bigger your pump(s), the longer 
you'll stay afloat. Big engine driven pumps are all well and good, but 
they're very difficult to install in the usual small sailboat engine 
cubbyhole, and, of course, the engine must start for them to be useful. 
Electrical pumps fail as soon as the batteries submerge. Manual pumps 
require a crewperson to operate, and that crewperson can't then 
otherwise help solve the flooding problem. Lots of bad choices. The 
usual wisdom is a manual pump that can be operated by the helmsperson, 
perhaps another good manual pump (eg, a big Edson) below, and an 
electrical pump or two. 

    For extra capacity has anyone ever used or considered using a macerator
    pump?  A Y-valve could be installed between the holding tank and the
    pump.  My macerator already has a through hull and shut off.  All I
    would need is a Y-valve and less than six feet of hose w/screen.  My
    Jabsco pump emptys my 30 gallon holding tank in about 3 minutes.  This
    represents a good additional pumping capacity.  Another advantage is
    that this type of pump will pass small objects as it is designed to
    grind waste down to a particle size of 1/8" should anything get past
    the screen.  I know this type of pump is not designed for continuous
    running, but when you need it, you need it.
    
    Good/bad idea????
    
    Chuck

    Chuck,
    
    Sounds like a good idea.  Macerators can move the stuff.
    
    What kind of power draw does one of those have?  You might need the
    engine running if you've got a bad problem.   Also, beware of depending
    on any macerator to pass small objects.  I've taken quite a few small
    objects out of macerators- tampons and bottlecaps to name a couple-
    that have caused them to stop running.  The screen would seem to be
    a useful addition.
    
    Dave

    The time has come to replace my manual bilge pump.  The two candidates
    are (1) the Whale Titan and (2) the Whale Titan MKII.  I think (1) is
    plastic and cheaper while (2) is metal and expensiver.  It's not clear
    from the documentation what differences there are in capacity.
    
    Any one have any experiences worth relating about these?  I'm
    particularly interested in how easy/hard it is to access the flapper
    valves for clearing.  My bilge is not famous for cleanliness and the
    debris that gets stuck in the valves frequently renders the current
    pump useless.
    
    - gene

    I believe the pump built into my Com-Pac 19 is a whale. There are 4
    screws on the flange of the intake and output connectors (1.5 in
    diameter) that when removed let the connectors come off, and the 
    flapper (intake) and "tricuspid" (output) valves are sitting right under
    the flanges
    
    Mine's the plastic one.
    Bill
    

I installed a Whale Titan (a plastic one) in my boat this year, replacing a
"Guzzler" pump, whose plastic body had cracked at the handle attachment.

I was impressed by the difference in weight between these two pumps. The
Whale pump uses much thicker plastic everywhere. All fasteners are through
bolts.

The Whale pump works very well. It has a good solid feel to it, and it pumps a
tremendous amount of water with modest effort.

One caveat: The bilge hose was a big part of the problem with the old pump. The
installation had a 10' length of the cheap white "accordion" hose on the
intake side of the pump, with about 3' of lift. When pumping, the hose would
contract and expand with each stroke. I got the distinct feeling that much of
my pumping energy was being expended on contracting and expanding the hose,
rather than lifting the water! I replaced the hose with a high quality
reinforced rubber hose, and it feels much better now.

The Whale pump has a generous opening size at the flapper valves. I think this
makes it less likely to clog. The pump is very easy to open. The diaphragm is
held in place by a large hose clamp around the diameter. Only one screw (on
the hose clamp) to undo, no loose hardware involved.

--RS

    I have a 1991 gear buying guide from PS with a bilge pump evaluation
    and rating.The comments of PS on one of your choises,the Whale Titan,
    reads:Disapointing performance.The best rated were the Edsons and a
    very innovating,inexpensive and good pump is the Henderson Mark V.
    On this pump you can easily remove the top and clean the inside.
    If you believe in PS and you like a copy send me your mail stn.and
    I will mail you one.

Specifications can lie.

I recently saw a report on several pumps. The real capacity once you put a
hose on the output is HALF of the specified capicity.

    Anyone know if Edson does a bulkhead mounted pump?  I recall their
    having a gallon/stroke floor model that can really move water. 
    However, it's too large for my application.
    
    - gene

    Your best bilge pump with top capacity is a scared man with a bucket.

    Don Casey in "This Old Boat" notes that the larger pumps, those with 
    1 1/2" hose for example, inevitably leave water standing at the bottom of 
    the bilges.  When the pump shuts down a substantial column of water sloshes 
    back down the hose. (Someone in another note complained about his large 
    automatic pump turning itself on every time the water ran back down the 
    hose and activated the float.)  
    
    Anyway, Casey quotes a U. of Rhode Island study on blisters and hull 
    delamination. It concludes that "prolonged stagnation of bilge water is 
    the surest method of destroying hull integrity."  Casey suggests a small 
    400 g.p.h. automatic pump at the bottom of the bilges -- one with a 3/4" 
    inch hose or even hose reduced to 1/2" just to keep the fiberglass dry.  The
    column of water returning to the bilges is small enough to evaporate
    quickly.  Above the small pump he mounted one of the Rule 3700s on a plywood
    bridge.  This pump is on a manual rather than automatic switch -- he
    reasons that if you spring a leak at your mooring the large pump will
    only run 6 hours or so without exhausting your batteries anyway.  
    
    I need a new pump and I'm intrigued by his two-pump idea, though making
    them both automatic makes more sense to me.  If a leak occurs while
    you are absent, say a couple hours before you arrive at your mooring, you 
    might stand a chance of saving your boat.  

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Note 763.31                What bilge pump capacity???                  31 of 41
SUBSYS::CHESTER                                      12 lines  20-MAY-1992 15:47
                                -< Second pump >-
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    I own one of the "other" type of boats but have the same problem.  I
    added a 500gph pump to the stern.  This the lowest spot but due to
    machinery, shaft, exaust there was only room for the small pump.  The
    larger 2000gph is in the front.  What I did for the wiring was to
    wire it in parallel with the large pump.  Used a 2.5A fuse  for the
    small pump.  With the auto/off/manual switch.  I can run the small
    one manually until the bilge is almost dry.  A second benifit is 
    the total capacity is now 2500 gph.
    
    
    Ken Chester
    

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Note 763.32                What bilge pump capacity???                  32 of 41
AIMHI::BORZUMATO                                     11 lines  22-MAY-1992 08:46
                                -< not enough >-
--------------------------------------------------------------------------------
    
    Boat u.s. just did a write up on bilge pumps, their capacities
    and so on.
    
    Might be worth your while to get a copy of it.
    
    Interesting.
    
    JIm  (i own a power boat as well)
    
    

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Note 763.33                What bilge pump capacity???                  33 of 41
SALEM::GILMAN                                        11 lines  22-MAY-1992 12:15
                       -< Pumps already there, use it. >-
--------------------------------------------------------------------------------
    A recent magazine just did an article about putting a Y connector (with
    a valve on each leg of the Y) connector on the input side of an inboard
    marine engines cooling water supply.  During normal operation the pump
    would draw from a seacock, during an emergency with flooding bilges one
    could shut off one leg of the Y and draw cooling water from the bilges
    instead... of course a strainer would be installed on the intake from
    the bilges, and, one would have to be careful that when the bilges were
    dry from pumping that the valves were switched over to draw
    seacock water before overheating the engine.  The point was that the
    increased pumping capacity in an emergency could save the boat. 
    

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Note 763.34                What bilge pump capacity???                  34 of 41
UNIFIX::BERENS "Alan Berens"                         23 lines  22-MAY-1992 12:54
                         -< on the other hand ...... >-
--------------------------------------------------------------------------------
re .33:

Yes, this is a common recommendation, and, in the view of others, a
wrong one. The usual rubber impeller in the seawater cooling pump will
be destroyed by only a few seconds of running dry. If you are busy
trying to cope with a serious leak, there is a high probability of the
strainer clogging or the of the water level dropping below the strainer
without anyone noticing. Once the pump impeller is gone, you will be
able to run the engine only briefly without overheating, which means no
battery charging, which eventually means no electric pumps, no radios,
no electronic navigation, no running lights, etc. Now your situation, if 
you're still afloat, is considerably more serious.

Besides, the sea water pumps on the usual small engine don't pump all
that much water -- mine is on the order of a couple hundred gallons an
hour. It would be much more effective to simply install an additional
electrical bilge pump. 

Your choice, of course. We've opted for two electrical pumps, two 
manual, and the engine sea water pump permanenetly connected to the 
seacock. 

Alan

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Note 763.35                What bilge pump capacity???                  35 of 41
HOTWTR::SASLOW_ST "STEVE"                             6 lines  22-MAY-1992 17:16
                      -< Big engines pump lots of water. >-
--------------------------------------------------------------------------------
    I read the article referred to. It recommended the Y in the intake of
    large inboard engines as an emergency high capacity pump in case of a
    hole in the hull to keep from sinking. I don't remember the numbers but
    the fact is that if you have a 3 or 4 inch hole in the hull, no
    store-bought normal bilge pump (or 4 of those) will keep you from
    sinking. A 2000 GPH pump will not even attempt to keep up.

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Note 763.36                What bilge pump capacity???                  36 of 41
DEMOAX::GINGER "Ron Ginger"                          22 lines  22-MAY-1992 21:38
--------------------------------------------------------------------------------
    >the fact is if you have a 3 or 4 inch hole in the hull, no
    >store-bought normal bilge pump will keep you from sinking
    
    Nor will the cooling water pump on the engine- did you ever look at
    the volume of water issuing from a boat exhaust? it probably wouldnt
    fill a bucket in a minute or two.
    
    If you really want to pump, you might consider hooking up a nice 2"
    bronze centrifugal pump with a good belt drive to the engine. That sort
    of pump could move some serious water- for leaks or fire fighting use.
    
    Think in horsepower terms- 1hp=746 watts. a 12 volt pump drawing a
    whole 20 amps would be 240 watts, or less than a third of a hp. Not
    much use in moving large volumes of water. Most of the small pumps
    referenced in this note probably dont even draw 10 amps.
    
    ALL electrical bilge pumps are for removing the casual leaks, like from
    a stuffing box, not for saving a holed boat. 
    
    There is no better pump on
    a small boat, in danger of sinking, than a bucket in the hands of
    a suitably worried man.

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Note 763.37                What bilge pump capacity???                  37 of 41
CHRCHL::GERMAIN "Improvise! Adapt! Overcome!"         6 lines  26-MAY-1992 09:56
--------------------------------------------------------------------------------
    I agree with most here that the Holy Grail of enough electrical pumping
    to keep a holed boat afloat is unreachable. The way I see it, the idea
    is to stuff a matress into the hole. Shore it up as best you can, and
    have enough pumping ability to handle the inevitable leakage.
    
    Gregg

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Note 763.38                What bilge pump capacity???                  38 of 41
SALISH::SASLOW_ST "STEVE"                             9 lines  26-MAY-1992 13:03
                   -< Big engines pump more than you think >-
--------------------------------------------------------------------------------
    Re: 36
    
    Yes, I have looked at the water coming out of my exhaust. I have 3.0
    inch diameter exhaust ports. At idle, they flow half full. At 2 or 3
    thousand RPM they shoot water like a fire hose. I know we are in the
    sailing conference where big engines are not in style, but my big V8s
    pump a lot of water and the article we are talking about was suggesting
    this for large engine power boats, not sailboats.
    

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Note 763.39                What bilge pump capacity???                  39 of 41
SALISH::SASLOW_ST "STEVE"                            11 lines  26-MAY-1992 13:10
                            -< Surprise, surprise! >-
--------------------------------------------------------------------------------
    OK, just to defend my statements, I happened to have a spec sheet on a
    Detroit Deisel 6V-92TA so I looked up the cooling system flow.
    
    Fresh Water Side = 185 gallons per minute
    Raw Water Side   =  92 gallons per minute
    
    Seeing that most store bought bilge pumps are rated in Gallons per
    Hour, that makes the raw water side 5,520 gallons per hour. A pretty
    hefty bilge pump. That says your 5 gallon bucket fills in a little over
    3 SECONDS
    

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Note 763.40                What bilge pump capacity???                  40 of 41
SALEM::GILMAN                                        15 lines  27-MAY-1992 15:08
                                   -< Pumps >-
--------------------------------------------------------------------------------
    I have to agree with the noter who suggested hooking a mechanical 
    drive from the engine to an auxilliary pump rather than going with
    an electric pump.  With an appropriately sized aux pump... say which
    would pump in excess of 1 gal per SECOND you might have a chance to
    keep your boat afloat with a moderate leak.  The best bilge pump is
    a scared person with a bucket is true... except people get tired...
    fast.  An engine doesn't, if you can keep it out of the water.  That
    extra big pump could easily be the edge that saves your boat.  Of
    course if you have knocked a 4 square foot hole in the bottom you
    are going to be damm lucky if you can do anymore than get off in a
    life raft before the boat vanishes beneath you.  Many of the accounts
    I have read of people getting holed via whales or reefs have at best
    several minutes to abandon ship.  
    
    Jeff

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Note 763.41                What bilge pump capacity???                  41 of 41
SUBSYS::CHESTER                                      17 lines  10-JUN-1992 13:09
                             -< Air bag for boats >-
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    From the June 92 issue of Offshore page 49.
    
    Ericson Safety Pump  To be the "air bag of boating".  The description
    say it works as an air blower sucking clean air into the engine room
    when ever the propeller shaft is turning.  In the event of flooding it
    becomes a 50,000 Gallon per hour pump.  A description of a demo was
    given where an 8" hole was made in 26' boat.  The pump kept it afloat. 
    
    The pump is fitted to the propeller shaft.  For shaft sizes 1" to 6".  
    A number was given for information.  212 265 1479 or fax 212 307 6857.  
    Ask for Karl Soderlund.   
    
    Interesting but how much does it cost?  No picture just a pen sketch 
    like the ones on patent app.
    
    Ken C