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Need advice for a second bilge pump

Posted: Mon May 11, 2009 3:59 pm
by mytrojan
I want to install a back up bilge pump. I was wondering:

* where would be the best place to install the second bilge pump? My current one is towards the bow by the drain plug.

* what flow rate (size of pump) do you guys recommend?

* I have a hand pump (manual) that Trojan installed as a backup. Can I use that plumbing for the new bilge pump?

* If I need to drill a new hole for the bilge water to exit outside the boat, should I drill it the same height above the water line as the original?

* I am a wimp when it comes to drilling holes thru the sides. Any special advice? just in the center of the plank, same diameter as the hose?

Posted: Mon May 11, 2009 4:29 pm
by guglielmo6160
I would install the pump in the lowest part of the bilge, if possible, and yes you can use the existing exit port,
you can exit the water any place above the water line, but ,,measure twice , think twice , and drill once if you have to,,,
I currenlty have three, two in the bow , , and one is using the hand pump exit, and I just installed another in the engine bilge, so Im covered, and I would get the one that moves the most GPH you can fit there, I think mine are 250 gph or something like that
you can never have to many,
what I did was make sure the aux pump is directly wired to the batteries, so if you have selection switches and you leave them off for some reason, the pump is always ready,
and always test them at least once a week, if possible,
at low tide, my marina is at 15 ft, so if they fail, and I take on water, Im going down
ya never know

Posted: Mon May 11, 2009 8:03 pm
by mytrojan
Thanks Bill
My (wood) 36' went in this past week and we almost had a real problem. The marina in Ithaca had replaced my auto bilge switch which was I believe was installed incorrectly- plus the slings were set a bit low. Water came over the floor boards in the cabin.

I see the need for a high water alarm and 2nd bilge pump.

bilge pump

Posted: Mon May 11, 2009 8:23 pm
by g36
in addition to my other pumps i have one at the stern of my f32. i would think if only having 2 pumps that this might be a good choice. while underway the boat will be stern down and any water that might come into the boat while underway will go there or at least the lowest part of the boat. if a hose or something sprung a leak or anyting else water related this might fill alot of the bilge if there are no pumps in the stern. but thats my thought. you might not know this till the boat slowed and levelled off. while underway i have had my stern pump come on a couple of times and i didnt think i had any water in the bilge at all but it was somewhere.

Posted: Mon May 11, 2009 8:46 pm
by gjrylands
I would install a manual switch plus a float switch and a pilot light so you know when the pump is running.

Posted: Mon May 11, 2009 9:45 pm
by kevin babineau
the more better has always been my motto...but it also gets me into trouble lol... a big boat should have aleast two bilge pumps as a minimum in my opinion...minimum...750gph as a minimum....if ur in a marina with alot of people around i would have aleast a float switch going to a buzzer or an alarm..mounted in a spot to say ...'hey my bilge pumps failed'...u can also attach it to a pump but u dont want the switch so low that the alarm goes off bc of rain water...like gjrylandsl said one pump should have a warning light so u can see it running...that way ull notice if that light says on longer than normal..... i keep on board a small house 110v pump..thankfully i havent needed for me but i have leant it out to other unfortunates...u can use ur existing thru hull if it is high enough from the water line.....inspect all used/old hoses and thru fitting if they are plastic...they will become brittle and not like being moved around...nothing sucks more than a dead battery bc the bilge pump aerated the bilge water..or worse...this is just my opinion :wink:

Posted: Mon May 11, 2009 10:06 pm
by guglielmo6160
one more thought, you know a friend told me that they now have a monitor module that will call your cell phone if bilge water is at a higher level than normal,
sounds like a real good idea and Im going to look into that

Posted: Mon May 11, 2009 11:24 pm
by MattSC
I have one in the bow area and added a second pump at the stern of the boat which is where all of my water goes once under way. I also added a T valve which lets me close the raw water intake in an emergency. I can then use the engine as another pump. It also makes it alot easier to winterize.

Posted: Tue May 12, 2009 6:01 am
by Danny Bailey
One other pointer: All bilge pumps should be powered through a fused source of 12v power. I have had a float switch hang up and the pump ran until the batteries were dead and the pump wiring was fried. Just luck that nothing was close enough to the wires to catch fire.

bilge pump

Posted: Tue May 12, 2009 7:17 am
by g36
guglielmo6160 one of the devices that your friend may be referring to is a company called boatsense. i have one and am currently trying to work out some problems with them and the unit. the unit and concept are good and it can alert you to some other things in addtion to th ehigh bilge water level by text depending on how you have it set up. but i cannot personnally recommend this yet, maybe when we get things worked out i can but not now.it is relatively inexpensive. there are other companies out there that can also do this but usually more cost

Posted: Tue May 12, 2009 7:50 am
by gjrylands
When installing the hose for the bilge pump, make sure you make a loop so the top of the loop is about two feet higher then the outlet. This keeps water from entering the fitting and back flowing through the bilge pump if the fitting ever gets under water. This could happen if the pump fails and the boat starts to sink. Without the loop water can freely enter the fitting and quickly swamp the boat.

Posted: Tue May 12, 2009 9:08 am
by mytrojan
Should I wire the new bilge pump fuse close to the 2nd house battery or the pump- or doesn't it matter where the fuse is....



Thanks for all the suggestions!

Posted: Tue May 12, 2009 9:27 am
by Dan Faith
Second one aft as was stated when running this will be the low part of the boat, mine has a third in the engine compartment. If your boat has the engine room under the living area it will be sealed off from the rest of the boat and should also incorporate an engine room bilge pump (a likely place for a leak from hose breakage or engine gasket leak. I also agree with a light to tell you which bilge pump is running.

Posted: Tue May 12, 2009 9:48 am
by kevin babineau
the fuse can be any where but the fuse usually protects what is in front of it...mostly the concern for a fuse on the pump is like someone said that it stuck on and melted the wires ..if it was me i would mount the fuse any where convient and out of the water but if near the source of power is convient then that would be my first choice

Posted: Tue May 12, 2009 6:29 pm
by guglielmo6160
Black Pearl
what kind of issues are you referring to with that device, you would think it would work, or not work? what kind of problems does the unit have? It sounds like a great idea and would love to know more