Second Bilge - One Way Valves? Please Advice.

[Mermaid]

Thank you soooo much. That is what I was thinking, I wasn't comfortable with the T and the ck valves were worrisome too. The thru hole is high up on the hull, almost to the deck, so we would have to be healing quite a bit to get water in. The second bilge pump was installed about 5 inches higher than the first one. I will definitely remove the valves when we put the separate line on next week. Thank you so much for all your time and info. You guys are great!

[CarinaPDX]

This thread is well timed, as I am doing a major refit. I have carried a 1-1/2" centrifugal pump with hose and quick electrical connection in a bucket for years, with a 1-1/8" centrifugal automatic pump and 2 manual pumps all independently installed. I have come to realize that even though I could quickly operate the crash pump, the short time required would still be better used to stop the leak. So I have mounted the crash pump as the main pump and have been considering something else to remove the small amount of water that ends in the bilge. Currently I am considering a Whale Gulper, as I have used one for a couple of decades to pump out the galley sinks and it has performed flawlessly.

While I certainly agree that bilges need to be kept clean - for all sorts of reasons - I have found that pumps and check valves have never failed even when I expected them to clog. The modern designs are incredibly robust. That said, please don't count on it - keep the bilges clean.

Check valves do more than prevent pump cycling; for manual pumps they maintain the prime between pumping. With air in the hose it takes a lot of pumping to prime - my cockpit pump has an input hose of about 10' length, which I don't really want to keep priming. However, I agree that using a check valve to prevent siphoning is a really bad idea destined for a bad outcome.

I regularly operated the manual pumps to confirm their status. Unfortunately this meant that water was left inside more or less continuously and corrosion developed inside the aluminum bodies. There is a lot to be said for plastic...

And I agree that there is an awful lot of undersize wiring around. My West bilge switch, rated at 15A, looks like it has 16ga cable. I will be dramatically shortening the leads coming out and replacing with 10ga or 12ga (for the larger pump).

Greg

[Wonderinlost]

Lesson learned and forget the guess. No check valves and use a vented loop. I like everyones experiences and sharing constructive knowledge. Thanks to all!

[chuckr]

late on posting this i guess - but when we put in our backup bilge pump we went big -- our orgininal is 1200gph (i think getting old and too lazy to it up) and is in a small sump -- we put in a second 4000gph with it's own control and it's own outlet - there is no way the smaller discharge hose would take the volume from the bigger pump - and we mounted it quite high so no problem with heel

[IdoraKeeper]

It is interesting to try to design a system for bilge pumps that covers all types of situations. The current system on my boat seems more oriented to pumping the bilge when the boat is unattended.... But the boat seldom has any amount of water in the bilge. If water was I introduced by wave action with the companion way open, it would trigger the high water alarm and start the pump, if the pump failed I can switch to the backup but it requires throwing a valve to route the output to the thru hull. I just realized that there is no means to silence the alarm other than removing the water.... Hmmm. I am working in that area already, I think perhaps it would be useful to have a guarded defeat switch available on the alarm circuit. No need to listen to the alarm sounding when I am already would be aware of the problem.

Crash pumps? I have three available on different circuits, each with its own thru hull. Still, if the leak is that bad stopping the leak is paramount. All thru hulls are accessible and the hammer and plugs as well.... A breach of any other kind may be much harder to deal with. Depending on the severity it might be time for the survival suits.