Anyone add a 2nd Bilge pump in the stern of their boat?

jip40

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I'd recommend making the second one a 'high water' or 'emergency' pump. This one would only need a float switch (makes wiring easy, too) and you would mount the float switch a few inches higher (an L-bracket/shelf attached to a stringer, for example) than the main pump. I'd also suggest making the emergency pump a higher GPH unit.

This is what I did on my 330. It is mounted above the standard bilge pump & below the batteries.

It has two alarms - one is the standard beeper type and the other is a red light that is mounted in the cockpit near the location of the pump.
 

seasick

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I am not sure I see a need for a second pump on the 208. In general the bilge is very dry (aft!). I could see a high water alarm or indicator though. My 208 does pool water up front somewhere and the only time I see that water run aft and trigger the aft bilge pump is when I launch it on the ramp at the start of a season When on the trailer, I can't get enough angle to cause the water to run aft. The drain tubes are not plugged, it is something in the design. Water probably gets in through the anchor locker and from the draining of the wet anchor line when used.
There is no easy way to get to the center bilge area without cutting access in the deck. Even then, i don't know how much room there would be or how the drain and through hull would be installed. I don't think there is a lot of space between the fuel tank and the helm/cabin bulkhead
I keep in mind that ishould a sea cock or hose break or burst or the hull was penetrated, the bilge pumps aren't going to be able pump out the amount of water that would come in. I also remind myself that although it would still be a major even if the hull filled, the boat will not sink.
 

DennisG01

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You're right that under normal circumstances, the HW pump should not be needed. And also right that if something catastrophic happens, those bilge pumps aren't enough. They could, however, give you just enough time to get back to shore. There's so many "in between" scenarios between no leak and absolutely catastrophic that there is a possibility that the second pump can make the difference. Think of a partly split hose that's below the waterline - something that is more than the regular pump can handle, but well within the capabilities of the HW pump. That brings up another good tool (aside from bungs/plugs/etc) to have... self-fusing silicone tape... Rescue Tape, for example.
 
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seasick

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Maybe I agree:) I do think that an alarm would be more advantageous since one would know that the bilge is filling and it may be time to put that PFD on!
If a seacock breaks off, the pumps won't help as we do agree. If the alarm goes off, put the inspection plates and if it is a hose, close the sea cocks. There are only two on that hull assuming it has the raw water washdown option.
 

mannoe

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Thanks for all of the great tips and suggestions about bilge pump installation. I just finished installing 2 new bilge pumps in my newly acquired Overnighter. The boat is an '88 and has seen a lot of service..."well fished" is the term I use...What I initially envisioned to be a quick and easy installation quickly turned into a major project. As I should have expected from a boat of this vintage, I encountered many interesting, creative and sometimes amusing "custom modifications" made by previous owners to the boat's original wiring system. These include the addition of various lengths and gauges of multi- colored hand laid wiring, plugged in or/or added to just about every easily available and conceivable location where 12v power can be tapped into. To clean up and sort it all out I must have cut out and removed at least 20 cumulative feet of useless added-on wiring. I will say that the knowledge and the hands-on practical experience I gained about the boat's electrical system was well worth the extra time and work invested. I've mounted both new pumps at the deepest point of the bilge. Both have built-in float switches. One is wired directly to the battery for automatic operation only, the other is wired through the boat's 12V service system and is set up for manual operation only via the existing bilge pump toggle switch at the helm instrument/fuse panel. This set up is pretty simple and requires minimal wiring. I will run the boat for a while with the pumps configured this way and see how it works out. Modifications may be needed. I'm also going to install quick release plugs in the wiring harness close to each pump to facilitate a quick swap-out when/if either one needs servicing or replacement.
 

DennisG01

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I'm also going to install quick release plugs in the wiring harness close to each pump to facilitate a quick swap-out when/if either one needs servicing or replacement.
Just an FYI... typically connections fail before the pumps. Make sure you are using high quality connectors and adhesive shrink tube. Also use the marine, tinned wire everywhere - regular wiring corrodes, even under the sheathing.
 
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DogBone

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To put the flow rates in perspective for a leak. Let's assume you forget to put in your drain plug. Assuming about a 3/4" diameter hole for the missing drain plug, and 24 inches below the water line results in leak of about 933 gallons per hour (GPH). Most bilge pumps are rated above that flow rate, so should be able to handle it or slow down the net intake of water. Obviously there are some leaks the bilge pump can't keep up with, but there are many common failure scenarios such as missing drain plug, and probably a broken hose that they can handle or at least mitigate for extra time. If you want to calculate the GPH for a hole D (inches) at a depth of H (inches), the formula is GPH=12.22*D*D*SQRT(768*H).

I ended up adding my high water pump, after I had the main pump fail due to its impeller coming loose from its shaft. The pump would turn on, but not move any water. Yes I discovered this when the boat was put in without the drain plug installed. I would have realized it sooner, if I had a high water pump with an alarm, or even just the alarm.

Dennis makes an excellent point about electrical connections being a common failure point. Crimped adhesive shrink tubing connectors are less likely to fail than removable type connectors.
 

seasick

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I will be going the connector route for my next pump mainly because every time a pump fails, when I cut the wire even right at the connector, it gets shorter and after several pump changes over the years, is becoming a pain to crimp on a new butt connector. The bilge pump in the 208 is a royal pain to work on since the only access you have are the two 6 inch deck plates in the motor well. You can't get two hands and arms in one plate and you need 6 foot arms to use both deck plates.
More importantly regarding the water proof connectors, the 208 bilge is very dry normally. Mine only gets water when I hose it or the rear lockers or if the deck plate o-rings wear out.. Rain water doesn't get into it usually. Regardless, I try when I install pumps, to keep the connections above the typical water level or float switch level. Even the adhesive butt connectors have corroded when subject to brackish water.
 

Ridge Runner

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Here is my set up, good, bad or ugly. Back-up Rule 1500 pump with high water alarm, about 9-10" up.
Pumps.jpg
Yes, I am replacing that hose, as soon as I find somebody that can reach that thru-hull! I paid to have that put in but didn't specify the hose...
I am not so concerned about while I am on the boat... You can feel it getting sluggish when there is a lot of water down below.
I want somebody to know if my boat is sinking at the dock!
I decided last night that I am hooking my high-water alarm (& pump) up to a switch.
While I am on the boat, the alarm will go off. While docked, it will sound the air horns!
The marina staff will be clued in about the air horns, and will instantly know what's up.
If nobody saves my boat from sinking, at least they will get it on U-Tube!
 

Sdfish

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Thanks again all. I'll be adding another pump, with high water alarm in my bilge. I'll mount the float a bit higher, but the pump will be at the lowest point.

Next question - what would you do? Use 5200 to mount a wooden pad to the bilge and install the pump on that or would you use 5200 to glue the plastic strainer directly to the bilge? I read both work - but am not too sure about 5200 directly on the plastic strainer.

I'll post picks when done.
 

glacierbaze

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You need the strainer basket submerged to pump water, not air, that's about 3/4 to 1 inch. Mounted on a block, that's another 3/4 to 1 inch. That's no longer the lowest point in the bilge, if that is really your goal.
There are one or more blocks glassed into the bilge , from the factory, for pumps, through hulls, etc.
 

DennisG01

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If you can't find a block already glassed in place (still use good sealant... or drill out and fill with epoxy)... Wood should be glassed, otherwise it will rot and you'll be left with a do-over. Marine ply will probably last the longest without being protected.

You could epoxy or 5200 a block of PVC (sticks better than HDPE) to the floor - that would be easy. I would not glue the strainer basket to the floor - that's another "do-over" waiting to happen if it breaks... even if just one of the latching "ears" breaks.
 

Sdfish

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Hi Dennis, I have a few pieces of fiberglassed wood blocks I was going to glue down with 5200.
 

DennisG01

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That'll work, Fish. As long as you have them on your workbench, figure out where the screws will go and do the "drill out and fill with epoxy" thing now. Make sure to run a bead of 5200 under the entire outer perimeter of the block to avoid water getting underneath.
 
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Holokai

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Kind of late to the party but I didn’t see it mentioned that the flow rate of your bilge pumps will also depend on the amount of head they’re seeing; depending on how your discharge hose is routed you can see a significant drop in actual versus published flow rate. This generally shouldn’t be an issue with normal amounts of water in the bilge but it’s good to know what your pumps are actually putting out. Here’s an article that explains things a lot better than I can.


To keep the bilge pump lasting longer I leave the plug in when washing up and fill the bilge with soapy water while flushing from any of the inspection plates. It allows me to verify the float switch is working and to run fresh water through everything. After cleanup is finished I jack up the bow and remove the plug to drain as much excess water as possible. Similar to seasick the bilge on my 208 stays pretty dry so I don’t feel a second pump is absolutely necessary if the pump is maintained well. If moored I’d consider a second pump wired to a different battery, though.
 
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Sdfish

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Thanks Holokai! Great article and appreciate you sharing. Will implement your bilge cleaning process as well. My 208 typically has a 1/2 gallon or so of water in it. Not much - but for some reason it irritates me. I think the water settles in the center of my boat at rest then flows back on when on plan. I like the redundancy of two pumps.
 

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I made a bracket out of stainless steel that screws to the transom or stringer with the float and the pump mounted to it. It makes it easy to unbolt the bracket and remove the whole assembly to service or rewire. It also keeps the float and pump at the same elevation and your float or pump is not tilted due to being bolted to the hull. There are also less mounting holes in the hull to leak water. Be sure to seal the 2 mount holes for the bracket. This is the one from my little boat. 1587085243464.jpeg