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Discussion Starter #1
I have a Rule non-automatic 1000 GPH with a standard float switch. Has generally worked OK, with some problem in cavitation when heeling.
What do you have, what do you like? Automatic w/integral switch? External switch, float, electronic? Brands?
 

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I like a remote switch if only to keep the pump in more protected place. Mine is a $130 Jabsco and it seems to work fine.
 

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Telstar 28
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It really depends on what you're going to be using said bilge pump for. The small ones with an integrated float switch are great for maintenance bilge pumps, where they just take care of the day-to-day drips and leaks into the bilge, but for an emergency bilge pump, you'd probably want it with an external float switch and much higher capacity.

Rule, Jabsco, etc. are all pretty decent, but just remember that the pump's GPH rating is usually for ZERO LIFT.
 

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I'm a recovering wooden boat owner so I know a lot about bilge pumps. ;-)

I have to say that without reservation I recommend rule. I tried a couple other brands and under my hard use/abuse they all died eventually. The two rules that came with the boat (1500 and 2000) were still going strong after 5 years of ABUSE. Once I came back from a week long trip and found it running dry with a stuck float switch. It was fine. They both saved the boat more times than I am willing to admit.

Switches are another issue. I probably went through 15 or so. The only one I really liked was the electronic switch by Johnson called the ultima. That and the old type that have a metal ball that you can hear roll from end to end when the switch is lifted. All the rest crapped out in no time.

Remember always have 2 (or more) electric bilge pumps wired to different batteries.

Medsailor
 

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Don't forget high water alarms. I use three WatchDog Water Alarms (LINK) alarms on my boat and they are very, very loud similar to a smoke detector and they can be heard over the noise of the engine! I have one three inches off the bottom of the bilge, one in the engine compartment and one in the head.

As far as bilge pumps go I think we need to be very careful taking any centrifugal pump at face value. Having two large pumps a wise idea with centrifugals!

Flow rates, as rated by bilge pump makers, can be quite misleading. They should serve only as a rough guide of a pumps "best case" capacity compared to others of similar design.

Bilge pump capacity is usually rated as “open flow” or what's called “open bucket” rate. This means the figures account for no, nada, zero vertical lift and also no discharge hose friction, radiused bends or discharge outlet restriction.

Actual flow rates, under real operating conditions, can be drastically lower. Water must be lifted up and out of the bilge and then be pushed through lengths of hose to the discharge point. This resistance is called head. Head pressure is basically the weight of the water and the frictional resistance of the hose, bends and outlet. Most centrifugal pumps, like the ones made by Rule or Johnson Pumps, have large internal tolerances to allow passage of bilge crap, so their flow rate decreases dramatically with increases in head. Unlike a vane pump, which would be less affected by head loss, the pumps rotor or impeller does not come in direct contact with the pumps walls. Impeller/vane pumps and diaphragm pumps are less affected by head pressure than a centrifugal pump is and they may actually be more effective despite a lower "labeled" GPH rating. Some of the vane/impeller pumps can handle 60+ feet of head pressure with ease. Because of the large tolerances in centrifugal pumps it can lead to, and create, cavitation if the head pressure is extreme enough.

I'm sure many of us have seen the bilge pump kick on and then not actually suck any water but instead just create noise and bubbles in the bilge. This can usually be eliminated by removing those ridiculous head boosting flow checks and the crappy corrugated bilge hose and replacing it with smooth walled hose..

The output of many centrifugal bilge pumps can diminish by as much as half with only a few feet of head and can stop entirely at between 13 and 20 feet, depending on the size of the bilge pump. Remember head is not just the peak height/lift of the hose it is the friction, height, bends and fitting restrictions all added together.

Another serious consideration is voltage. What is your pump rated at? Is it 14.2 volts or 12 volts. This will and can make a difference as the pumps motor increases and decreases output based on voltage.

There have been a few tests like the ones conducted by West Marine. They rated pumps based on voltage and head pressure. Most manufacturers ratings (open bucket / no head ratings) were off between 10-50%. the output on average was reduce by about
5% for every foot of head pressure. With voltage the drops from 13.6 volts to 12.2 volts were another 15-30% off on top of the head pressure loss. So your 800 GPH centrifugal pump may not even deliver 1/3 of that rating in a real word situation..

I guess what I'm getting at is this; unless you have a "monster truck" grade bilge system, do not count on anywhere near the face value rated capacity from your bilge pump.

Some other things to consider:

- Use smooth walled discharge hose as it has significantly less head resistance than does corrugated.

- If the discharge outlet is close to the waterline you must use a high loop in the discharge hose to prevent siphoning. It is advised to add a siphon break at the highest point to ensure it won't siphon. Even with a high loop a bilge pump can still siphon without a siphon break. I have been on more than one boat that self siphoned when under sail and power.

- Do not succumb to the temptation of using a "check valve" with a centrifugal pump. If you have 5' of height, in a 1" hose, the pump will more likely than not cavitate before it can throw open that check valve with that standing water behind it..

Disclaimer: Many years ago I used to sell a line of submersible pumps to the plumbing and well supply wholesale distribution channels.
 

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I have a Rule "automated" pump in a boat that collects a lot of rain water. It has an internal sensor that makes the pump come on when the water level rises and keeps it running 20 seconds after the water level drops so it cycles less. I don't like seperate float switches as they can get pinned under someting that prevents them from coming on, or get something stuck under them so the pump never goes off and leaves you with a dead battery. On my old wooden boat, I had Lovett pumps that worked hard, and never failed. If I had room, they'd probably be my first choice.
 

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We have the Ultra Sr. pumpswitch by Ultra Safety Systems, and from everything I have heard or experienced they are bullet proof. A bilge pump is pretty important of course and the Ultra Sr. has a High water alarm. Our is sent way down into the bilge.
 

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pump placement question for Mainsail???

QUOTE:

- If the discharge outlet is close to the waterline you must use a high loop in the discharge hose to prevent siphoning. It is advised to add a siphon break at the highest point to ensure it won't siphon. Even with a high loop a bilge pump can still siphon without a siphon break. I have been on more than one boat that self siphoned when under sail and power.

- Do not succumb to the temptation of using a "check valve" with a centrifugal pump. If you have 5' of height, in a 1" hose, the pump will more likely than not cavitate before it can throw open that check valve with that standing water behind it..

Disclaimer: Many years ago I used to sell a line of submersible pumps to the plumbing and well supply wholesale distribution channels.[/QUOTE]

Mainsail: I wanted to ask you about having the discharge close to the waterline. I will be installing a Whale pump that is designed for shallow bilges. I'd like to 't' into the sink discharge through hull which is only about 4 feet from where the pump will be and I'll avoid having to create another hull opening. Will I still need to put high loop in the discharge hose even if the pump has a check valve?

Thanks
 

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Discussion Starter #9
yes, high loop

I'll chime in on the question to Maine Sail. Yes high loop, because if the check valve fails, you gonna have a wet boat.
Practical Sailors sister publication, Power Boat Reports, tested a bunch of pumps and reported data on much of what Maine Sail is talking about 20 Electric Bilge Pumps Tested
I do have a check valve because the discharge line is Tee'd into the shower sump line and then the single line has a vented loop. I will probably give it it's own vented loop then tee the lines right before the thru hull.
One of my main interests in the original question is the switching. Integral within the pumps certainly seems less to maintain. The electronic ones would seem to offer better reliability.
 

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1977 Morgan OI 30
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Don't forget high water alarms. WatchDog Water Alarms (LINK)[/URL] alarms on my boat and they are very, very loud similar to a smoke detector and they can be heard over the noise of the engine! I have one three inches off the bottom of the bilge, one in the engine compartment and one in the head.
Thanks for the tip Maine Sail! I didn't know about water alarms and will get one for the boat and my basement. Inexpensive too via Home Depot. And the smooth hose makes sense too.

Thanks Pamlicotraveler for the tip re Ultra Safety Systems. I use Rule but will grab one of those switches! ...good post!
 

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Believe it or not, there is no bilge pump installed on production Gemini's.

The shower sump pump (250gph) has a T valve in a locker on the port hull and hoses that extend to each hull; you can uncoil the hose and use it to vacuum out any loose water that makes it into our 4 inch deep bilges. The pump drains via a t valve in the head's sink drain.
Fortunately Gemini's are dry boats.

I keep promising myself that some day I'll install a real bilge pump but running a hose to topside is going to be a real problem. For now I have a 1500 gph Rule wired to a 12v plug that has a hose long enough to reach my cockpit as a just in case (there is a 4 ft head for those that are interested). I also use this for anchor washdown, just throw the pump overboard, plug it into a 12v plug in my anchor locker and use the hose end to spray away mud. It's not fresh water but it's better than nothing.

BTW the Ocean Cat A certified version of the Gemini has a manual pump in the lazerette, switchable to either hull and a 1500 gph electric pump in each hull. They can't retrofit the installation once the hull liner is bonded in which is why I'm having a hard time figuring how I'll route the hoses.
I may just go with a check valve and a hose to the centerboard slots, but if the check valve fails my boat would sink about 2 feet.
 

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QUOTE:


Mainsail: I wanted to ask you about having the discharge close to the waterline. I will be installing a Whale pump that is designed for shallow bilges. I'd like to 't' into the sink discharge through hull which is only about 4 feet from where the pump will be and I'll avoid having to create another hull opening. Will I still need to put high loop in the discharge hose even if the pump has a check valve?

Thanks

I never like to tee into a below waterline anything for a bilge pump and I also never recommend a sink.

#1 Below waterline fittings can become clogged and or have the flow reduced by sea growth.

#2 When you leave the boat one should always close the seacocks. If you close the seacock the bilge pump will just fill the sink and over flow back into the boat.

#3 Sink drains especially can become clogged with food, hair, tootpaste and other gooey items that when mixed with aquatic life begin to reduce the ID of your plumbing and reduce flow or increase head pressure.

#4 I never advise the use of tee's. Always use a Y adapter if you absolutely, positively must share a line. I hate to ever see a bilge pump on a shared discharge.

#5 I stand by what I said about check valves they do nothing but add a potential failure point.. They are notorious for not opening and causing the pump to cavitate, not move any water and killing batteries..

It's your boat but please do think through all the possibilities.. and yes you still need a high vented loop!!!
 

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water line through hull

thanks for the input. Just to clarify, my sink through hull is just above the water line and is only sitting under water when the boat is heeled on a port tack. And yes, I meant to say I'd use a y valve and wasn't intending a pure 't'. Given that my boat has no automatic pump right now, I thought I'd go ahead and take advantage of the hole that is above the water line, and then remedy this properly when I next have the boat on the hard. I just haven't decided if I should add a through hull midship just below the toe rail, or extend a pipe all the way to the transom. The only existing holes at the transom are also just above the water line for the scuppers.
 

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Hi there Maine Sail. I have a small ranch in east texas and am looking to pump water, using a 12v pump and solar panel setup out of a creek from mid sept to november. I am needing to do this in dry years, I have a seasonal creek, which is about 22' deep and will need it to work when the season is dry and there is not much water moving in the creek. Do you think a 12v vein pump would do this or do you have any suggestions? I was thinking of using my 45 w of solar panel's coupled to a diesel truck deep cycle battery, 12 v float switch and one or 2 pumps (1000 gph or so), with flotation riding on a pipe concreted into the bottom of the creek with a larger ID pipe riding on the other pipe.

Any suggestions for me please? You are obviously a man that knows his pumps. No issues here in texas in removing water from a creek for irrigation of livestock.

Thanks RJ
 

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Just FYI, you may already have the hoses for the bilge pumps installed ... they were already installed with the wiring on s/v Felix IIRC, and all Frank did was add the pumps and wire them to switches.

Believe it or not, there is no bilge pump installed on production Gemini's.

The shower sump pump (250gph) has a T valve in a locker on the port hull and hoses that extend to each hull; you can uncoil the hose and use it to vacuum out any loose water that makes it into our 4 inch deep bilges. The pump drains via a t valve in the head's sink drain.
Fortunately Gemini's are dry boats.

I keep promising myself that some day I'll install a real bilge pump but running a hose to topside is going to be a real problem. For now I have a 1500 gph Rule wired to a 12v plug that has a hose long enough to reach my cockpit as a just in case (there is a 4 ft head for those that are interested). I also use this for anchor washdown, just throw the pump overboard, plug it into a 12v plug in my anchor locker and use the hose end to spray away mud. It's not fresh water but it's better than nothing.

BTW the Ocean Cat A certified version of the Gemini has a manual pump in the lazerette, switchable to either hull and a 1500 gph electric pump in each hull. They can't retrofit the installation once the hull liner is bonded in which is why I'm having a hard time figuring how I'll route the hoses.
I may just go with a check valve and a hose to the centerboard slots, but if the check valve fails my boat would sink about 2 feet.
 

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I have a Rule "fully automatic" I think it is called. It comes on every several minutes and if it senses load on its impeller it keeps pumping. Works very well, and I like it because there is no float switch to fail.

However, this is best if you have shore power or some other system of charging your batteries when you're not sailing. After a few weeks it will lower your battery.
 

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What about maintenance?? I have a RULE 5 year 3700 and a wooden boat....it's getting a work out now.

I have it disconnected and am cleaning the bilge.....is there anything I can/should do to the pump? Is there anything to clean/inspect?

Thanks,
morgan
 
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