Bilge Pump And Setup

[danblu]

Hi folks,

I'm concerned about the bilge pump not having an huge capacity and also has not an automatic system installed. I wonder if there is agreement on the ideal setup, capacity. Mine is a 32 foot Atkin's Thistle. She has a deep well aft of the engine. The bilge pump is a feeble affair with a manual switch. Also have a manual pump in the cockpit. Is there a simple , affordable setup with huge capacity?

[JeanneP]

I think we need to define some terms. What do you mean by huge capacity? What are you hoping to accomplish?

I just went to the West Marine on line catalog to look at bilge pumps. They come in various sizes and configurations. 500 gallons/hour (gph), 570, 1000, 2000, 3700 gph. Fully automatic, not automatic. float switches, submersible.

So what do you think you need? I personally think that for your boat 500 gph would probably be fine. Do you live aboard, or is the boat unoccupied much of the time? What do you think will happen while you're gone? What do you have to power the pump? A large capacity pump running off a small battery isn't going to accomplish much when the battery dies.

Play "what if" - what kind of leak do you think will happen? How much inflow from that leak? How long before you discover the problem?

Until you define the problem you are going to have a hard time defining the solution.

[danblu]

I guess a problem with this type of yacht the engine is below the water level. I have 390 amp hours at 12 volts. I worry about coming back and finding her on the bottom. Now I see that there are these rather cheap looking pumps that actually reside in the sump and there are the type which can draw water up a couple of metres and so can be fixed to some structure well above the water line. Maybe a system that uses both types would be best. Smaller capacity in sump type for day to day use and a large capacity above the waterline type with a switch set higher for emergency use. I was hoping for some feedback as to the systems aboard the yachts owned by the Noble Folks who frequent this forum.

[JeanneP]

Before we moved on board full time we kept sv Watermelon on a mooring, and each weekend when we went out to her I was so relieved that she was still afloat!

My worries were just a tad overblown. Not because of our bilge pump setup, which was pretty standard, a 500 gph pump with a float switch.

When we left the boat every Sunday night we went around closing all the through-hull fittings. Not only did that close the holes that could let water into the boat, it tested those through-hulls, something that took a lot more discipline after we moved aboard.

If you have been aboard your boat while a survey of the boat was being done, you might remember that the surveyor checked each of the through-hulls, and tested each one as well to make sure they opened and closed easily and didn't leak. Although I don't have any data to back up this theory, I think that failed through-hulls are the major cause of a boat sinking on its mooring or in its marina berth. Each of our bronze through-hulls was bonded to the boat grounding system, and our zincs were inspected frequently and replaced before they were completely gone.

After all, if a through-hull fails mid-week, by the time you get back to the boat the battery will have been run down to nothing, the pump will have failed, and your boat will have sunk. Better to close those holes and leave the pump to take care of the trickle that might seep through the shaft seal, or some unknown deck leak.

We now have a power catamaran, and some of the issues on the sailboat repeat themselves on the power boat. We have a hot water heater that heats the water through a heat exchanger with our engine cooling system. The water gets really hot, and one of our mistakes has been not turning off the fresh water system when we were running the engines. Another was forgetting to make sure that the bilge pump switch was switched to "automatic".

When the water in the h.w. heater gets really hot and pressure builds up, the excess pressure blows out water through the pressure relief valve. If the water pump is left on, the pump refills the water in the tank, it heats up again, the expansion blows out more water, and over an 8-hour period several gallons of water are spilled into the bilge. Though the bilge pump switches are usually on "automatic" they are rocker switches that occasionally get rocked the wrong way, to the "manual" setting. Imagine the dismay when going into the engine compartment to check the oil and find water in the bilge. Fortunately I'm not afraid to taste the water to determine if it's fresh or salt, so we know what happened pretty quickly, or at least what we were looking for.

And then there was the day that we forgot to turn off the pressure water switch, made an 8-hour run, and discovered that even with the bilge pumps on automatic we still had water in the bilge. That time, it turned out that one of the bilge pumps had failed.

Complacency is an affliction that hits us all at some time or another. That bilge pump worked perfectly for several years and we stopped thinking about testing it occasionally.

[danblu]

Thanks Jeanne,

Mines on a berth with power so the battery charger should look after the current. The charger can put out 40 amps at 12 volts if needed. I recently changed the heads, which was built out into the saloon. I removed the pump through type of toilet and replaced with a large potty type, so we can use it on her berth. After rearranging the bulkhead we were left with two seacocks under the table. Well one had been touched by someones foot and the next day when I came aboard and checked the bilge it was about full of salt water. I immediately pumped it out using both the electric and the hand operated bilge pumps. What I found was that one of the seacocks had been slightly leaking all night! I've since stopped the ends so that it cannot happen again. I'll remove the cocks next season when I put her on the hard.

That gave me quite a fright so am thinking about how the ideal setup might work. I see you do have two pumps aboard. Or is it just one in each hull?