R21 second bilge pump

ohioan55

Well-known member
Joined
Aug 25, 2015
Messages
210
Fluid Motion Model
R-23 (Outboard)
Hull Identification Number
FMLT2314C424
Vessel Name
Jersey Girl
I've installed a second bilge pump and wiring in the bilge void forward of the engine. I ran into a snag routing the discharge hose. I had intended to route it up to under the sink and splice it into the sink discharge. Problem is that there is no fairly direct route to the sink from that void as the space between the cockpit pan and hull will not accommodate a 3/4" hose to fit (or a 5/8"). I can easily route the hose aft (and have) under the engine into that area aft or the engine where there is space. I have 3 choices for discharge to finish the project and this is where I am seeking others opinions. One is to splice into the primary bilge pump discharge (easy, but the issue with this choice is obvious). Two, make a turn and route the hose forward along the port side of the hull where it will fit and splice into the sink discharge as originally planned (meaning about 20' of discharge hose). Or three, add another discharge on the port side under the cup holder (another hull penetration). Two pumps sharing the same discharge is an easy solution, but the idea of 2 pumps sharing the same discharge could be problematic. The 20' of hose could be a problem as well, but can be done as with ease. And any new hull penetration should always be well thought out and considered essential before drill touches hull, but could be easily done at this point. Ok, the floor is open..
 
If you check the space just to the port of where the electrical wires from the stripper pole are you will notice a area that you can pass a hose to the sink drain. You may have to notch out the board used for the deck of the cabinet. That run of hose would be about 3ft. If you PM me or better to text me and ill send you a picture. Bob
 
Well................

What needs to be kept in mind is that any bilge pump system already in place is designed to only handle that load or rate of discharge. Maybe it could handle a little more?? If both pumps turn on at the same time you may not get the rate of flow that you want. That becomes a bottleneck. Also one pump could back flow into another but I will not get into that.

Your best bet is that each pump has it's own hose and thru-hull. Use a hose with smooth inner walls, it will help keep the rate of flow up. Keep hoses as short as possible.

Don't think that a rated pump is going to give you that amount of flow. If the thru-hull is two feet higher than the pump and the length of hose will play into it too. The pump will need to work harder giving you a lower rate of discharge. So a 1000 gph pump my only give you 800 at the thru-hull.

Anyways, good luck with the project.
 
Iggy, that is my concern with 2 pumps trying to pump out the same discharge. I would like to have it share the same discharge as the sink, which would eliminate having to cut another hole in the hull (last option in my book). I am using a smooth wall, chemical resistant, re-enforced vinyl type hose (3/4" ID), which should work well. The junction with the sink hose will reduce some flow.

Bob, I'll go look at that path again as it would seem to be the best path. I have an AC unit in that space above the water tank, but squeezing a hose through that hole in the corner next to the stripper pole wiring bundle may work.

Thanks to both for the response.
 
In doing the same second bilge pump install, I went to the Starboard side.
Our head has a disconnected Macerator pump (we are in fresh water and it must be disconnected).
I ran the pump to that thru hull (with the loop).
I know the fuse panel is close but that is where the factory put the head discharge.
Plumbing to that was fairly simple but I did add clean out ports to the cockpit steps.
I also pulled the frig to run the hose, that may not be needed (but it is easy).
Hope this offers another option.
 
Well, I did finish the install and ran the hose aft under the engine and then to the port, lopping back forward and then to the sink discharge. I did add a Jabsco checkup to keep the sink from draining into the bilge, but all testing went well. I added a image on my album. Thanks to all..
 
I need to look at this. I have had water up to the deck twice due to Ultimate switch failure, this of course sets off the high water alarm which than kills the battery. Not fun. I would like the second bilge pump located higher so it does not activate unless the first one fails. Where would you consider locating it and would you consider a different manufacturer bilge pump.
 
I have a picture in my album under mods. I bought a Seaflo and mounted it in the bilge forward of the engine. And I powered it off of the bank 3 (AC) batteries. For discharge, I routed the hose and connected it to the sink discharge via a Y fitting. If you need pics, I can send them to your email. PM me with it, if you wish.
 
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