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Author Topic:   Sump Pump Breaker Trips
2communicate posted 12-25-2010 09:33 PM ET (US)   Profile for 2communicate   Send Email to 2communicate  
Something strange has happened to our 1998 17-foot Outrage (1998). I'd left the cover off and we experience about five days of heavy rain. When I went to take the boat our for a bay cruise, I first drained the anchor cubby through-hull, the two drains in the engine bin, then the drains underneath each of the back seats.

The bilge was full of clear water, and I was using the pump to drain it, when the pump shut off. I found the breaker had opened, so I closed it and resumed pumping, but it opened again. I opened the pump, thinking the impeller might be fighting something, but it turned easily. I was taking people out for a cruise, and was running out of time, so decided to leave the bilge about half-full.

During our bay cruise, running now faster than 7 [nautical miles per hour], water started to overflow out of the bilge onto the deck. I brought the boat back to the dock to figure out what was happening. Since the bilge pump was still operating only intermittently, I used a bucket to empty the bilge. I then saw that a steady stream of water was running from the small hole just below the top of the bilge on the starboard side, filling the bilge again. Also, water was streaming into the bilge from around the wiring harness for the bilge pump.

Did the Whaler take in a lot of rain water and store it in some compartment in the hull? Is that what was draining into the bilge? And also causing problems with the bilge pump wiring?

Where is this water coming from? Any help would be much appreciated!


Jerry Townsend posted 12-26-2010 01:32 AM ET (US)     Profile for Jerry Townsend  Send Email to Jerry Townsend     
David - I have a 1996 17 Outrage, and I suspect about the same boat. Water has filled your fuel tank cavity. There is a nylon threaded plug immediately above the sump pump - that may be hard to see - but it drains the fuel tank cavity into the sump. Remove that threaded plug so that water can drain into the sump. Now, getting rid of the water in the sump - you have a few choices since your sump pump is not working reliably - with the sump thru-hull plug removed, trailer or raise your boat, run the boat to evacuate the water or use a submersible pump to remove the water.

And all of the above assumes that the sump thru-hull plug was in and tight.

With your sump pump tripping the breaker - the sump pump may be faulted, and, if so, replace it. But you first have to drain the water. --- Jerry/Idaho

jimh posted 12-26-2010 10:31 AM ET (US)     Profile for jimh  Send Email to jimh     
On your electrical problem:

A circuit breaker in a branch circuit controlling a sump pump should not open during normal operation of the sump pump. Your conditions are abnormal, and you need to investigate the cause of the problem.

The sump pump may be faulty and drawing too much current. This typically occurs if the pump is stalled. Give us more information about the rated current drawn by the sump pump and the rating of the circuit breaker that is tripping.

The circuit breaker may be faulty and could be tripping at a current that is lower than its rating.

There could be other loads on the circuit which are creating additional current in the branch circuit, causing the circuit breaker to trip. The wiring to a sump pump should be insulated and protected so that it can operate when the sump area is filled with water, however, it may be possible that there is a problem in the wiring which is creating an additional load. If this is the case, you want to investigate this immediately because any leakage of battery positive current into the water will create galvanic corrosion, which will shortly become a much more serious problem than the sump pump circuit breaker tripping.

On your terminology:

A Boston Whaler boat hull does not have a bilge, and it is not correct to refer to the various molded sump areas in the hull as a bilge space. A Boston Whaler hull is a double-bottom hull, and the area between the inner and outer hulls is filled with foam. There is no access to this area, and there is no free space in this area for water to collect. In other boat hulls this area would properly be called the bilge area, but not in a Boston Whaler boat.

Your boat likely has a cockpit sump, which is a low area designed to collect water that drains into it from the cockpit. This sump typically has a drain through the hull bottom to the sea. It is also typical that a sump pump is located there to pump water overboard, and the pump may be operated by a float switch or other automatic mechanism.

Your boat also likely has an engine splash well, an area designed to collect water that has splashed over the transom and drain it back to the sea. I believe this is what you intended to indicate when you referred to the engine "bin."

The area where the anchor stows is usually referred to as an anchor locker, not as a "cubby."

On Boston Whaler hull design:

Boston Whaler hulls with internal fuel tanks have those tanks located in a fuel tank cavity, typically on centerline and in the cockpit area. These cavities can collect water if the level of water in the cockpit rises and overflows the cockpit sump. Once water flows into the fuel tank cavity there is typically no easy way to remove it, other than by evaporation. For more discussion on the design of the fuel tank cavity on your particular boat, you should begin a new discussion in a REPAIRS/MODS discussion, as that topic is not related to small boat electrical systems.

On the drains in a Boston Whaler hull:

Consult your owner's manual for advice on how to manage the drains in your Boston Whaler boat. In particular, the cockpit sump drain is often recommended to be left open if the boat is left unattended and outdoors for long periods of time. In this way, any rain water that collects in the cockpit will be drained overboard.

2communicate posted 12-26-2010 11:21 AM ET (US)     Profile for 2communicate  Send Email to 2communicate     
Thanks, Jerry and Jim, for your helpful replies. All that you said makes sense and now I'll be able to talk about the Whaler with more appropriate terminology.

I'm headed down to the boat later today, and have one remaining question. It sounds like the water leaking in around the sump pump's wiring harness is coming from rain water collected in the fuel tank cavity. I'm wondering whether the 1/2" drain about 3" below the top of the starboard side of the cockpit sump is designed to drain water from the same area?

I don't have a trailer for the boat - it sits in the water year around - so draining water requires slightly more effort than tilting a trailer, but it's all doable.

Best holiday wishes.

jimh posted 12-26-2010 11:32 AM ET (US)     Profile for jimh  Send Email to jimh     
The cockpit sump drain typically opens to the sea through the hull bottom. If you open this drain, sea water will rise in the sump to a level that depends on several conditions. If the boat is heavily loaded in the stern, it is possible that sea water will rise in the sump to almost the top of the sump, and this may also permit some water to fill the rigging tunnel. (The rigging tunnel is typically connected to the cockpit sump.) However, in most cases, the sump will contain the water entering from the hull drain. In this way, you can leave the drain open all the time. There will be water in the sump, but it will not rise above the level of the boat waterline. If there is heavy rain, the rain water will drain out of cockpit, into the sump, and into the sea.

When the boat is underway, water will drain from the sump due to the Venturi action of the bottom end of the drain and the water rushing past it. If you have someone with you, you can run the boat onto plane, and let all the water collect and drain from the sump via the hull drain. While still on plane, put the drain plug back in place. You will have drained all the water in the cockpit and sump.

When the boat is at rest, and while you are standing over the sump, the water line will be higher, and you may get more water in the sump than you anticipate. Step off the boat, and observe the water level in the sump with no one aboard. This will be the static water level when the boat is unattended.

What is the current rating of the circuit breaker that is tripping?

What is the current rating of the sump pump?

2communicate posted 12-26-2010 11:45 AM ET (US)     Profile for 2communicate  Send Email to 2communicate     
Jim: I don't know anything more about the sump pump other than I believe it is rated at 500 gallons/hour. It has worked for several years without a problem, and, once it started triggering the breaker, I've taken it apart to confirm that the impeller is running free. My guess is that the rainwater is somehow interfering with the electrical current, but I'll know more later today. When I first turn it on, it will run fine for about 2 minutes, then it starts to intermittently trigger the breaker. If I leave it on, the breaker finally opens for good and I haev to manually reset it.

The drain I am asking about is not the sump drain you are referring to, which has a diameter of closer to 1". The drain I am wondering about is smaller (about 1/2" in diameter) and located several inches higher in the well.

jimh posted 12-26-2010 12:03 PM ET (US)     Profile for jimh  Send Email to jimh     
The smaller opening may be a cross-connection from a rigging tunnel on the other side of the cockpit.
jimh posted 12-26-2010 12:07 PM ET (US)     Profile for jimh  Send Email to jimh     
A circuit breaker trips open based on two factors: current flow and time. Typically if the current flow is only slightly greater than the rated current, the breaker will take a longer time to trip open than if the current is substantially greater than the rated current. For example, if a circuit breaker is rated to trip at 10-amperes, it will trip open very quickly if a current of 20-amperes flows, but if a current of only 12-amperes flows, the breaker may not trip open for several minutes.

To learn what is really happening with the circuit powering the sump pump, you should measure the current flow in that branch circuit while the pump is operating. Then compare the current flow to the rated current flow of the pump and the rated current of the circuit breaker.

Jerry Townsend posted 12-26-2010 05:31 PM ET (US)     Profile for Jerry Townsend  Send Email to Jerry Townsend     
David - your first problem is - getting rid of the water - and then correcting the pump problem. And right now, you know the sump pump will not operate adquately.

One thing you might try is to siphon the water out of the sump. Take a short (5 - 10 feet) piece of garden hose, put it in the sump and completely fill the hose with water, put your thumb over one end of the hose and rapidly pull that end from the water and over the side at the lowest point and then remove your thumb from the hose. Hopefully, water will flow from the hose - if so, make sure the end of the hose in the sump is at, perhaps weighted with a brick of something, the bottom of the sump. --- Jerry/Idaho

Jerry Townsend posted 12-26-2010 07:06 PM ET (US)     Profile for Jerry Townsend  Send Email to Jerry Townsend     
David - One thing I forgot to mention - make sure the sump thru-hull is plugged. ---- Jerry/Idaho

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