Bilge Pump Thru-Hull Location

[JWS]

I know it isn't ideal but some rv antifreeze dumped in the bilge with the pump running buys you some protection from freeze up... Until it cycles again anyway.

 

[Crusty Coastie]

Like John said , if they are low like that make sure the line loops up high , or has anti siphon etc , I was moving a sailboat and the bilge hose had been shortened many times so on a starboard tack it would back and fill with water , quite exciting at night in a strange boat

God forbid that they spend the $20bucks and twenty minutes to change it instead of adjusting their man bun for an hour.

 

[lobstercraven]

Like em just under rubrail ahead of main bulkhead

I like them on the helm side of a lobster boat. That way I can keep an eye out as to when the pump comes on and what’s coming out. There can be Lots of important information coming out of the bilge. I want to see it

 

[BlakeH]

I like them on the helm side of a lobster boat. That way I can keep an eye out as to when the pump comes on and what’s coming out. There can be Lots of important information coming out of the bilge. I want to see it

This is why I’m moving it in the first place. It was at the transom and I like to be able to see it

 

[BSEA]

For what it's worth, I recall some bilge pump install instructions call for a minimum of 12" above waterline for discharge outlet.

 

[leaky]

For what it's worth, I recall some bilge pump install instructions call for a minimum of 12" above waterline for discharge outlet.

And for good reason

 

[LadyMaureen]

I ran my rear lazarette pumps (primary and secondary) to discharge underneath my gunwhale at transom....this way I always know when the pumps are going on. The switches with lights are great but they are 30 ft away at the helm. When I am in the cockpit I see the pumps come on and dump water onto the deck near the scupper. Some may disagree, but I will never not do this, I love the concept. Good luck.

 

[Diesel Jerry]

I like them on the helm side of a lobster boat. That way I can keep an eye out as to when the pump comes on and what’s coming out. There can be Lots of important information coming out of the bilge. I want to see it

Same as all my dad’s lobster boats. Up high and visible. Doesn’t do well for a dockside princess though.

 

[Clarke]

This is probably a dumb question, but could bilge water be sent out the exhaust along with the cooling water? As long as they don't feed back to each other? Anti-siphon / check valves?

 

[Diesel Jerry]

This is probably a dumb question, but could bilge water be sent out the exhaust along with the cooling water? As long as they don't feed back to each other? Anti-siphon / check valves?

No because of the risk of exhaust gasses coming through the bilge pump plumbing.

 

[Clarke]

That makes sense. Yes, probably one of those things not to keep hidden anyway. At least if its up high, the sound of running water hitting the sea surface tells us something is up!

 

[Crusty Coastie]

I ran my rear lazarette pumps (primary and secondary) to discharge underneath my gunwhale at transom....this way I always know when the pumps are going on. The switches with lights are great but they are 30 ft away at the helm. When I am in the cockpit I see the pumps come on and dump water onto the deck near the scupper. Some may disagree, but I will never not do this, I love the concept. Good luck.

My Laz pumps out at the tuna door ramp and is check valved.Good to see its actually going when you've been backing on a fish for a while and theres been a foot or so in the cockpit a few times.

 

[Fouraces59]

I like them on the helm side of a lobster boat. That way I can keep an eye out as to when the pump comes on and what’s coming out. There can be Lots of important information coming out of the bilge. I want to see it

Absolutely, One day the oil pressure sending unit cracked and oil was leaking into bilge. Having the discharge on side with helm where I was hauling gear, let me catch it quickly and shut things down. Quick tow in and fix and were back out hauling gear in the afternoon. Never want bilge discharge where I can't see them easily

 

[Kailua Kid]

Absolutely, One day the oil pressure sending unit cracked and oil was leaking into bilge. Having the discharge on side with helm where I was hauling gear, let me catch it quickly and shut things down. Quick tow in and fix and were back out hauling gear in the afternoon. Never want bilge discharge where I can't see them easily

I had a nasty case out on Guam involving a boat that sank at the dock in the night. The bilge pump through-hull was located at the waterline, for cosmetic reasons. The in-line check valve failed when a small bit of bilge debris held the valve open after the pump cycled. A small wake introduced seawater. There was no anti-siphon loop. The boat sank before dawn. Constructive total loss. Hundreds of thousands of dollars. The owner was fined under the OPA ‘90 Clean Water Act over the resulting oil and diesel discharge into the harbor. Huge fine. Nasty, nasty.

For me, no bilge through-hull even near the waterline. Never rely on a check-valve to keep water out of the boat at any angle of heel or any potentially loaded condition. Also, as noted above, having the bilge discharge where the outflow can be observed while operating the boat (both for flow rate and for content, but also for frequency) is my preference. Just my two bits. Others on here are much more knowledgeable than me on this topic (and nearly every other topic).

 

[Toolate]

Like em just under rubrail ahead of main bulkhead

I like that you can see the water coming out if you are at the helm

 

[Alext123]

I am in the process of redoing my bilge and wondered why one of the pumps discharge was forward of the main bulkhead?