How connect two bilge pumps to ione thru hull

[Terra Nova]

So many unsafe and poorly thought out bilge pump installations among the posters here.

[boatpoker]

Originally Posted by Aaaskypilot

I have 2 Rule 2000 on my 32 ft. Gulf, both have check valves about 10” away then go to aY fitting & out to the back thru Hull ... Each is wired on separate circuit thou for the safety back up if one were to fail in use

sounds ripe for a siphon issue. This is one of the reasons ABYC are against such an installation.

[GILow]

Originally Posted by Terra Nova

So many unsafe and poorly thought out bilge pump installations among the posters here.

Which would at least have a CHANCE of being a constructive post if you indicated your preference.

But sitting back and sniping isn’t really helping anyone since we don’t even know which you think is good and which is poor.

Let alone WHY.

[Terra Nova]

Originally Posted by GILow

Which would at least have a CHANCE of being a constructive post if you indicated your preference.

But sitting back and sniping isn’t really helping anyone since we don’t even know which you think is good and which is poor.

Let alone WHY.

While you busy yourself criticizing the posts of others you have missed a lot that's already been said.

[GrahamO]

This is also my preferred option. No interdependence and a good warning (wet feet....)

Originally Posted by rbk

I’ve always been keen on dropping the emergency (higher in bilge) pump into the cockpit, that way you have a kiss built in alarm if the water is rising or when it is subsiding.

[allene222]

The OP requested input on what other people do but did not specify his setup so what I do may not be relevant and probably violates every rule there is. I have one large through hull that was on the boat when I got it with a manual pump. I wanted to add an automatic pump but did not want to add a through hull. You all will hate this but as it works and is probably novel so I thought it worth posting. I have two T connections with a check valve between them in the main line from the automatic pump. The manual pump then connects to these two T connectors. The manual pump has two check valves in it by design so I don't see how one could eliminate check valves. In any event, the automatic pump water goes through the two T connections and through that check valve without going into the manual pump. There is a third pump that is low capacity and will pump down to 1/2 inch or so. The automatic pump cannot empty the sump because of all the water that flows back that was in the large hose. The small pump has its own small (garden hose) line that goes through a high check valve and on to a T right at the through hull. The small pump fails every 4 1/2 years and my bilge fills with water up to where the large pump float switch is. That just happened this month so I am replacing it later today. I also have a portable manual pump and a bucket. I gather from reading this thread that I have violated every rule you guys have but the system works and has more pump capacity that the boat had when I got it, which was my goal. PS. I always buy the extended warranty which gives me 5 yeas so I get new pumps for the $14 cost of a new extended warranty.

[Bbolino]

Don't do it.
Too much potential loss for too little gain
Either you install a bunch of plumbing including check valves which can fail or you have to pump one or both to a spot you probably shouldn't pump them too

I will take the simplicity and reliability of an extra above the water line through-hull

[Terra Nova]

Originally Posted by allene222

...I have two T connections with a check valve between them in the main line from the automatic pump...

Very poor tech and unsafe.

[FionaJC]

Having been called to my boat as the bow was six inches down and going on board I fould water 9" above the lower deck I have a strong opinion on bilge pumps.



I already had an manual pump and automatic aft & centre electric pumps switched and to thier own outlets.



The aft pump switch and the centre pump had failed I think about three weeks previously, I regreased the leaking stern gland fitted the centre spare pump and went back a week later. The gland was still leaking slightly and the spare pump had failed. I replaced the pump with a new one, a week later the centre switch failed.


Because of the comments here I now have the following arrangement .


Aft - automatic switch to electric pump, on domestic battery. own outlet
Centre - automatic switch to electric pump, own outlet on domestic battery, own outlet
Centre - second automatic switch at higher level to electric pump, on starter battery battery, own outlet


I also have an Arduino with GSM module looking at battery voltages, water levels centre and aft and pump run times. It texts me every friday lunchtime the state of batteries and total pump run times. If it the levels go up to high on centre or aft if sends me an emergency text.


Im adding gas, fire and intruder detectors.



My strong opinion? Seperate pumps on seperate circuits of power and pipework. The Rule pumps have built in non return valves too (for fence sitters). All skin fittings are well above waterline.



I sleep more easily now.

[Caliber40]

Pumping bilge water into my cockpit seems a bit strange to me. It would take me all of 10 seconds to cross that off the list!

[HorizonMarine]

As previously mentioned it is rather easy to connect two bilge pumps to 1 through hull. It would require 2 one-way valves and a tee fitting or preferably a y fitting. If your goal is to have 2 pumps in case one of them goes out or malfunctions then this will work nicely. If your goal is to have an emergency set up when you are taking on water, this is not a good idea because you are limited by the size of the through thru-hull. We have done this job dozens of times over the years and the is no problem. That being said, on my own boat I have separate lines with separate thru hulls. It is certainly the preferred the system. Has an FYI you can put a through hole in your boat while it is in the water. Just takes some in the water with a plunger and another person working from above. We can actually put a through hull in a boat with less than a cup of water coming inside.

[boatpoker]

Originally Posted by HorizonMarine

We have done this job dozens of times over the years and the is no problem.

That suggests that you are a marine service provider, if so, don't you follow ABYC Standards.

[CapnJackB]

Are we trying to fix something that is not broken?

[MJH]

Originally Posted by xxhat

Want to eliminate one thru hull.
Right now each bilge pump has its own thru hull.
Was thinking of eliminating one by having each pump go to a sea chest then the sea chest goes to the thru hull.
What are others doing ?
How else can I eliminate one thru hull ?
maybe by having one pump go to the cockpit ?
Thanks

jim

Very few details about your boat situation to put your request into perspective, i.e. why do you need/want to do this?

That said, your thought goes against prevailing boating wisdom: one thruhull for each bilge pump and you already have that.

Some boaters just look for problems that aren't there. I don't see any upside to what you want to do or why.

Leave good enough alone.

~ ~ _/) ~ ~ MJH

[rbk]

Originally Posted by Caliber40

Pumping bilge water into my cockpit seems a bit strange to me. It would take me all of 10 seconds to cross that off the list!

This is for your emergency bilge pump not primary. It should be located at a higher point than your primary and is a backup when your primary cannot handle the ingress of water. As mentioned alarms are another option, if you're able to hear it from the cockpit in a blow or over the sound of your engine. This is the bilge pump you never want to see turning on.