Bilge pump placement

Matt19020 · Post by **Matt19020** » Wed Dec 19, 2007 7:16 pm

I am planning to put a bilge pump in my "M". I was thinking that the best place to mount it would be just aft of the battery compartment under the bunk. Does this seem to be a reasonable position....meaning- the "low spot" in the bilge?
I was thinking of putting the thru hull fitting at the stern just above the water line. Or is it better to come thru the side of the boat just above the water line?
Any advice would be appreciated before I start drilling holes.... Thanks

atzserv · Post by **atzserv** » Thu Dec 20, 2007 1:18 am

I too need to put a pump on my 06M. From some reading on this site I think you are on the right track with placing it aft of the battery compartment. Some have even mentioned 3 locations. The point I wanted to relate to you is that I read where splicing into the sink drain is an option. Nice because no added holes. But I recall that a check valve inline with the sink drain line may be needed "a backup issue". I hope this post stirs up others to help you along, as well as myself getting further advice.

Gary

Currie · Post by **Currie** » Thu Dec 20, 2007 5:31 am

I need to add one someday too. I think the actual low point is just aft of the daggerboard/permanent-ballast. I haven't checked if it's practical to have a pump there (i.e. under the galley for me, under the forward settee seat for you). I might need to add a small length of siphon tube, which you could probably do from behind the battery compartment as well. Also, I would imagine the low point shifts somewhat with loads.

Cheers,

~Bob

delevi · Post by **delevi** » Thu Dec 20, 2007 10:28 am

I believe the lowest spot is all the way aft where the rudders are. If you had water in the bilges, that's where it eventually ends up. You would need to remove the two pannels adjacent to the steering gear to see this area.

Leon

Paul S · Post by **Paul S** » Thu Dec 20, 2007 10:39 am

I don't know about T'ing off the drain..as you would need 2 one way valves. If either stick you might have an issue. I would avoid one way valves on a boat if I could help it.

Still haven't put a bilge pump in our 04. Was thinking of adding a through hull fitting somewhere coming out the stern. other ideas? Where have others put it

Paul

Catigale · Post by **Catigale** » Thu Dec 20, 2007 11:02 am

Check valves suck. Use through hull shut off valves - I confess I used house plumbing fittings from Home Depot at 4USD each

Chip Hindes · Post by **Chip Hindes** » Thu Dec 20, 2007 5:39 pm

I have three separate bilge pumps; one in the center one on the outside of each of the longitudinal stringers. With the boat heeled you could have literally hundreds of gallons of water below a center mounted bilge pump. Even when it's straight up you can get 20-30 trapped by the stringers.

Mine are all controlled by a single on/off switch on the panel; no float switch. They are the cheap Rule type but are advertized as being OK to run dry, so I leave the switch on as long as one of the three is pumping.

I personally think it is an especially bad idea to tee into the sink drain and I feel the same way about check valves on a bilge pump. Each of my three is plumbed to its own thru hull on the starboard side just above the rub rail. It's additional head for the pumps but I will never have to worry about water coming in thru the fitting. Here's a shot showing the thru hulls at the right edge of the photo. The fat guy in the water is me.

Matt19020 · Post by **Matt19020** » Thu Dec 20, 2007 6:50 pm

I am not sure if I like the sink idea. I never did like check valves they only time they seem to work perfectly is when they are in your hand before you install them.
Chip you make sense about the angle of heal and and the lack of performance associated with only installing one pump. It will be something to think about.

Paul S · Post by **Paul S** » Thu Dec 20, 2007 7:34 pm

what about mounting the thru hull high on the transom?

Catigale · Post by **Catigale** » Fri Dec 21, 2007 4:03 am

I put my through hulls just below the chine to minimise head. I have shutoffs inside that are normally closed when sailing.

Paul - I also put one on the transom with trap loop to prevent backflow - I dont have a valve on that one since its hard to access.

Chip Hindes · Post by **Chip Hindes** » Fri Dec 21, 2007 12:03 pm

You could put your thru hulls on the transom, which would presumably put them lower than where I put mine over the rubrail, but then you'd be pumping a considerably longer distance. Both height and distance contribute to head. Seven of one, half a dozen of the other.

I like mine where they are because I barely have to lean over the side to tell if they're still pumping water, so I know when to shut them off. I suppose I saved a few bucks on the discharge line which, if you buy the good stuff (not the cheap corrugated stuff form Walmart) is not cheap.

That being said, I guess I see no good reason not to mount them on the transom as long as it's at a point that is always above the waterline. You might be surprised how high that is when the boat begins hobby horsing over short period swells. BTDT.

Steve's method of shutoffs works too, compared to putting them higher up, but I like the idea of just being able to lean inside and flip the switch on when I first climb onto the boat, let it run a few seconds to check for discharge, then flip it off if none. I admit that I have never resealed the windows or the chainplates on my seven year old boat, so I can get a surprising amount of water in the the bilge from nothing more than a period of heavy rain.

Divecoz · Post by **Divecoz** » Fri Dec 21, 2007 9:53 pm

My experiences have been different than those above.
I have one pump for now its next to the battery under the ladder. It does T into the sink drain and I have a check valve.
First off I cut in too close to the sink and I pushed water into the sink.
I moved the T to within a foot or so of the transom and all is well now . I was getting water in thru my thru hull (IMHO Mac put that unnecessarily to low ) I installed a $14.00 pvc check valve I got at some boat store. For now so far. . . all is well.
As for the numbers of pumps ??? I agree with Chip 3 would be best. I will install 2 more this year . The one I have is auto-check and it too will run dry. It works off load resistance to operate.

beene · Post by **beene** » Sat Dec 22, 2007 4:48 am

I have had a leak in my M since day 1. Still have not nailed down where it is coming from. I have a pump and plan to mount it just aft of the battery compartment as that is where the water has always collected to date. The only good news is that it seems to be just from rain, rather a hole in the bottom of the boat.

I plan to just run it off a switch in the cabin and drill a hole in the stern above waterline for the through hull drain line.

I have noticed that water also collects in "secret places" that you can't see, probably beneath the main cabin floor between the ballast tank ribs. When I motor and purposely tilt the motor up and gun it, pointing the bow into the sky, I get quite a bit of water draining from those secret places into the area beneath the aft berth. So I figure I can do that for a few seconds, back off on the throttle and sit still, turn on the pump and dry her out.

Wish I did not have this problem at all though.

Oh well, roll with the punches right?

G

Divecoz · Post by **Divecoz** » Sat Dec 22, 2007 7:34 am

beene wrote:I have had a leak in my M since day 1. Still have not nailed down where it is coming from. I have a pump and plan to mount it just aft of the battery compartment as that is where the water has always collected to date. The only good news is that it seems to be just from rain, rather a hole in the bottom of the boat.

I plan to just run it off a switch in the cabin and drill a hole in the stern above waterline for the through hull drain line.

I have noticed that water also collects in "secret places" that you can't see, probably beneath the main cabin floor between the ballast tank ribs. When I motor and purposely tilt the motor up and gun it, pointing the bow into the sky, I get quite a bit of water draining from those secret places into the area beneath the aft berth. So I figure I can do that for a few seconds, back off on the throttle and sit still, turn on the pump and dry her out.

Wish I did not have this problem at all though.

Oh well, roll with the punches right?

G

Beene since put in the check valve I no longer find water in those secret places.
I was getting water in thru my bilge pump. I have two switches on my pump. 1 is an over-ride manual run and the other is an auto check.
I have to turn the auto check off at night to sleep. The motor spins for 2 or 3 sec.'s ever 90 sec.'s to check for the presence of water. I forgot to turn the pump back on, the worst day I have ever had out on the water.

Catigale · Post by **Catigale** » Sat Dec 22, 2007 9:06 am

Mine are all on ON OFF AUTO switches which let you run the pump or let a float switch trigger the pump when water collects in the bilge. Until I found my corroded compression post was leaking water my pump would click on every 30 minutes or so. I positioned the switches so I can see the pilot lights from the cockpit and see if I am taking on water.

AUTO at night
ON to manually pump
OFF on trailer

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Bilge pump placement

Bilge pump placement

Bilge Pump