Bilge Pumps vs Bilge Pumps

[RoJack1]

I have recently acquired a 42' wooden hull Constellation. She has a good sound hull, completely re planked four years ago, but the rest of the vessel will be a complete restoration and refit. My most immediate concern is the bilge pump set up the last owner was using. (A single pump discharging thru flex hose out of a window) Since the boat is in the water, and will be unattended for long periods of time, my first project will be to install a four pump system, following the rule of thumb of one pump per every ten feet of boat. My question is, and I realize I will get a lot of opposing opinions, which is more reliable. Automatic pumps, or manual pumps wired to float switches? The system will be battery powered with and automatic battery charger hooked to shore power. I am also going to hard pipe the system to proper thru hull fittings with check valves at each pump. Any opinions on using PVC pipe for this purpose? It seems to me, that the smooth inner walls of the PVC would create less restriction of flow than the flex pipe that comes with most pumps while still having enough give to withstand flexing of the hull.

[perchance]

What size pumps and how much water do you expect to take on?

[RoJack1]

The hull is pretty tight with no more seepage than you would expect in a wooden hull. My main concern is that the boat will be unattended for several weeks at a time. I was planning on going with four two thousand GPH rules. There are three seperated compartments so that accounts for three of the pumps. The fourth will be in the engine room (the largest in bilge area) and will be mounted six inches higher than the other pump as a back up. I realize 2000 GPH pumps are probably a bit of overkill but I would rather have to much than not enough when that tremendous rain storm comes and I am all the way across country from the boat. The boat is not in a covered slip and there is a lot of topside work to be done.

[Stillraining]

Welcome Aboard RoJack

Id go with 2 electric and two manual if your really concerned about it...One manual operated from the cockpit and the other below deck.

You say 3 compartments but don't you just have one blige?...If so Id mount one higher then the other by a few inches like you say but also have that one sound an audible alarm..one that can be heard from the dock.

[Chief Engineer]

I raised a boat this winter where the owner used PVC pipe below the waterline.

The lines froze....pipes burst....boat sank

[Kashmir cat]

My boat is left unattended for long periods of time and although the people who work at the marina are very conciences, I still worried about leaks and other problems that might not be discovered until it was too late. That's why I bought the "Boat Nanny" vessel monitoring system. It monitors high water in the bilges along with a myriad of other things like intruder alert, temperature, fire, etc. It sends a daily text to my phone or computer giving a status report and immediately notifies me of any problem. In addition, I have installed a bilge counter (BilgeWatch 8) that monitors all my bilge pumps (up to eight) and tells me how many times each one cycles on and off in a given period. It also will notify me if any of the pumps cycle more than normal in a set period of time.

[Boracay]

Assuming you had the boat surveyed recently what did your surveyor recommend? If he has not made any recommendation can you call him up and ask?

Assuming you have insurance what does your insurance company require?

One very good bilge pump may be better than multiple poor ones. There have been a few reports of switches failing when cycled on and off repeatedly so if you can get a setup where the pump only comes on very week or so that may be better.

Don't forget that the wiring has to be sized to handle a heavy load, and the battery needs the capacity to run the pump for a while. Investing in a solar cell to keep the battery charged and maybe even upgrading to deep cycle types (you may need to do this soon anyway) may be a better way to go than multiple pumps.

[Chief Engineer]

At most marinas around here...they will call you if your boat is sinking...but will take no initiative themselves.

Gotta love those lawyers.

[DeepFrz]

I think PVC pipe is fine so long as it is connected to the thru hull and to the pump with flexible hose so there shouldn't be any stress on the pipe itself. As for the multiple pumps I would stagger the float depth so that one (perhaps smaller) pump will empty the bilge of normal water.

[swisscraft]

Hi, if the boat is long time untended I would add a backup to the backup - smaller pump, with separate battery and solar charging - in case of shore power failure it may run some extra days.

cheers Marco

[capt_douglas]

I'd use hose that has a smooth interior to reduce drag for the pickups and some kind of trash filter on each, just in case. You can connect the output of two to one big hose for pumping over the size. It's important to remember that the flow/pump rate for those pumps is not real world, as many tests have shown.

As for the automatic/float switch problem, both have been known to fail. I've used both but have in the past doubled up on the sensors, just in case one of them went bad while I was away.

Many folks get better drainage by having two different pump capacities in the bilge - a smaller one for low down and a biggie for the upper. This way the smaller will drain most of the water and have less backflow but the biggie will do the heavy lifting if the smaller got overwhelmed. And I'd wire the float switches separately to each pump.

[Dockhead]

Originally Posted by RoJack1

I have recently acquired a 42' wooden hull Constellation. She has a good sound hull, completely re planked four years ago, but the rest of the vessel will be a complete restoration and refit. My most immediate concern is the bilge pump set up the last owner was using. (A single pump discharging thru flex hose out of a window) Since the boat is in the water, and will be unattended for long periods of time, my first project will be to install a four pump system, following the rule of thumb of one pump per every ten feet of boat. My question is, and I realize I will get a lot of opposing opinions, which is more reliable. Automatic pumps, or manual pumps wired to float switches? The system will be battery powered with and automatic battery charger hooked to shore power. I am also going to hard pipe the system to proper thru hull fittings with check valves at each pump. Any opinions on using PVC pipe for this purpose? It seems to me, that the smooth inner walls of the PVC would create less restriction of flow than the flex pipe that comes with most pumps while still having enough give to withstand flexing of the hull.

A couple of suggestions.

No check valves on the discharges. Make sure and have an anti-siphon loop.

Use proper flex hose, double clamped.

Don't run all the pumps off the same battery bank.

Automatic switches are a weak link. We use Ultimate Juniors, which are very expensive, but according to our research are the only ones which are half way reliable.

Put in alarms.

Read this: ALL ABOUT BILGE PUMPS - Boats, Yachts Maintenance and Troubleshooting

[RoJack1]

Originally Posted by swisscraft

Hi, if the boat is long time untended I would add a backup to the backup - smaller pump, with separate battery and solar charging - in case of shore power failure it may run some extra days.

cheers Marco

Sorry I haven't been able to thank folks for there input till now. I am one of those that actually has to work over the holiday weekend. I like the solar power idea. In fact I was talking to a guy about that yesterday. One of the jobs that needs to be done topside is to rip off the entire pilot house roof and replace it. There is no fly bridge so the pilot house roof would be an excellent place to mount some solar panels. I have to admit though, that I know very little about solar power. By the time I get around to replacing that roof though, I can learn.