Bilge Pump Hose Location

[l008com]

So, since this boat was new some 25 years ago, this is how the bilge pump was set up. The hose comes up from the pump, through a hole, and into the area in front of the motor. That area has a small hole that slowly drains the water.

See Below:

But woudln't it make more sense for the water to come out the side of the boat, where it wouldn't get stuck in a 'holding area', and instead would flow right out into the body of water? Like near the left side of the red stripe in this picture?

Assuming the answer is yes... What kind of adapter or valve do I need? I assume some kind of plastic insert that you insert into a drilled hold, probably that you glue into place, then clamp the hose on to with a hose clamp.

 

[JimS123]

Re: Bilge Pump Hose Location

That's not a factory setup. Rube Goldberg at best. The hole that is used for the pump hose should be sealed so water does not go into the bilge area. Water from the splash well should drain overboard, usually thru a hole thru the transom.

Drill a hole thru the side of the boat, as high as possible just under the rubrail. Locate it as far aft as possible. Use a thru-hull fitting and connect the pump hose to it - don't just stick the hose thru the hole....LOL.

 

[l008com]

Re: Bilge Pump Hose Location

It is indeed a factory setup on 80s thundercraft outboards. Or at least, every one I've seen. And these were common on the lake back in the late 80s. But anyway, that "pan" area the hose drains into is angled, so realistically very little water ever actually splashes back in. And there is a hole thats you can't quite see, that drains that area. It's not quite as bad as you make it sound.

But ok, so what kind of thru-hull fitting? Where would I get one. How do I install it properly? Will the height of the hose cause an issue? I know that the pump can easily lift water the high up, but when the pump turns off, won't that mean more water is going to fall back down the hose?

 

[109jb]

Re: Bilge Pump Hose Location

It is indeed a factory setup on 80s thundercraft outboards. Or at least, every one I've seen. And these were common on the lake back in the late 80s. But anyway, that "pan" area the hose drains into is angled, so realistically very little water ever actually splashes back in. And there is a hole thats you can't quite see, that drains that area. It's not quite as bad as you make it sound.

But ok, so what kind of thru-hull fitting? Where would I get one. How do I install it properly? Will the height of the hose cause an issue? I know that the pump can easily lift water the high up, but when the pump turns off, won't that mean more water is going to fall back down the hose?

Any store that has boat supplies will have through hull fittings. Bass pro, Cabellas, Gander Mountain, any boat dealer, etc.

 

[l008com]

Re: Bilge Pump Hose Location

I found them on this site. Even some chrome ones, fancy.

 

[JimS123]

Re: Bilge Pump Hose Location

Sorry, but I never saw a factory setup that was that crude. The type of fitting you need is the type that would be supplied with a bilge pump kit. It is a threaded fitting with a barbed tube, to accept the bilge pump hose. Chose the size to fit your existing hose. Like this one:

http://www.iboats.com/Thru-Hull-Str...68526491--**********.521756455--view_id.56451

 

[Fireman431]

Re: Bilge Pump Hose Location

That very well may have been some type of factory set-up, but it was an after thought at best.

The only water that will come back into the bilge, which is the amount in the hose between the pump and the fitting (5/8" hose x 3' = approx 3 cups of water). Not nearly enough to even consider. Aside from that, install a backflow valve inline with the hose and get nothing back into the bilge.

 

[cr2k]

Re: Bilge Pump Hose Location

You won't get that much water drain back down the hose. Not really a concern.
A lot of outboards drain as yours in to the "engine well". Very common. But it would be better to drain overboard via a thru hull fitting. Just put a little sealer around the outside flange before you insert it. Most use a large nut from the back side to secure. Attach your bilge hose and put a SS hose clamp on it.
The problem with the way yours is set up is water from the engine well aka splash well can enter the bilge through the funky shield around the hose.
You are showing some smarts by wanting to correct this situation!

 

[l008com]

Re: Bilge Pump Hose Location

The biggest issue I see with the current setup, is that while the water comes out of the hose good and fast, it drains through the second hole kind of slow. Its never been an issue, but if a big wave climbs on board to say hi, it will be tough getting that water out quickly, it will just overflow the splash well and drain back in.

 

[Home Cookin']

Re: Bilge Pump Hose Location

after you correct that incorrect factory set-up, seal that hole. That is an important safety issue--the splash well compensates for the low transom cut for the motor, but there are many circumstances where unwanted water can fill the splash well. If it goes to the hull, pump or no pump, you can swamp.

 

[Fireman431]

Re: Bilge Pump Hose Location

After changing the discharge, I would cut that hole larger and add the deck plate. This way, you could actually reach into the bilge and replace the pump/wiring/dig out dead rats, etc.

 

[ajgraz]

Re: Bilge Pump Hose Location

Agreed to cover that hole in the "floor" of the splashwell. IMO that's a damned dumb place for the mfgr to put a hole.

As I see it, you got two choices:

1) Hose (turquoise) from pump (pink) makes a drop loop (through an anti-siphon valve, orange), to a through-hull (green) 2 or 3 inches above waterline:

2) Hose simply rises to a through-hull minimum of 12 inches above waterline:

My bilge used to spill into splashwell also (though from a side wall rather than the bottom); I'm going to go with option #2 above, and use this 3/4" thru-hull (though in black):
http://www.iboats.com/90-degree-Thr...23390936--**********.565032252--view_id.40099

 

[Home Cookin']

Re: Bilge Pump Hose Location

WADR I would not do option 1; it's over-engineered. Too many points of failure and high risk of a through hull that low. Anti-siphon is not a concern if you put the hole high enough. No worse than what he already has!

 

[Beefer]

Re: Bilge Pump Hose Location

Option #2 will work just fine. There are many (myself included) that feel strongly against any type of backflow device in a bilge pump setup. There is that chance that something can obstruct the valve from opening, and then you've got gallons of trouble.

You can always put a loop in the line if you want for the peace of mind.

 

[Fireman431]

Re: Bilge Pump Hose Location

Where can I buy a pink bilge pump, turquoise tubing, and a pale green thru-hull fitting? All I ever see are white & black!!

 

[l008com]

Re: Bilge Pump Hose Location

After changing the discharge, I would cut that hole larger and add the deck plate. This way, you could actually reach into the bilge and replace the pump/wiring/dig out dead rats, etc.

Look again at photo number 2. That is extremely unnecessary I'll just find something to plug it with.

Agreed to cover that hole in the "floor" of the splashwell. IMO that's a damned dumb place for the mfgr to put a hole.

As I see it, you got two choices:

1) Hose (turquoise) from pump (pink) makes a drop loop (through an anti-siphon valve, orange), to a through-hull (green) 2 or 3 inches above waterline:

2) Hose simply rises to a through-hull minimum of 12 inches above waterline:

My bilge used to spill into splashwell also (though from a side wall rather than the bottom); I'm going to go with option #2 above, and use this 3/4" thru-hull (though in black):
http://www.iboats.com/90-degree-Thr...23390936--**********.565032252--view_id.40099

Yes so I'll also be going with number 2. But question. Is there a reason you have the exit port so far forward? Or is that just for illustration purposes? I was going to drill my hole not only way up on the red line, but also way back, like only a few inches from the transom.

 

[l008com]

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[ajgraz]

Re: Bilge Pump Hose Location

Just for illustration purposes. Although on my boat there's a huge wad of flotation foam under the stern cap such that, unless I cut a bunch of it out, I have to put my thru-hull that far forward.

 

[l008com]

Re: Bilge Pump Hose Location

I ordered a fitting and a new hose today. I figure i'll run the hose UP higher than the hole, then down a few inches to it. That way I don't have to worry about any really odd situations splashing water into the hole.

 

[Home Cookin']

Re: Bilge Pump Hose Location

don't put too much of a rise; no more than an inch. It will adversely affect efficiency. Think about it: if that hole is under water, your transom opening is way under water. A little spray up the sides ends up in the bilge to be pumped back out. If you get a lot, you have bigger problems.
Add a float switch while you're at it, if you don't have one.