FAQs

Will a Sun Pump work in salt water?
The Sun Pump is designed to pump rainwater from open fresh and saltwater based boats. While it has not been officially tested in high humidity, high moisture conditions, it is fabricated from marine components, stainless steel fasteners and all electrical contacts have been treated with dielectric grease. 
Where should my Sun Pump be placed in my boat?
The Sun Pump should be placed at the rear of your boat, next to the transom. The outlet hose is connected to the pump, which draws rainwater through the bottom of the Sun Pump box. The pump end of the box should be situated flat in the bottom of the boat with the hose extending up and over the transom. The end of the hose can be affixed to the lift handle with the adjustable velcro strap.

How long can a Sun Pump pump?
The battery is rated for 7 amps and the 500 GPH bilge pump consumes an amp per hour so theoretically, it could pump for 7 hours. It test pumped for 7 hours but I recommend just 4 hours of continuously pumping. Just how much water is that? Well, lets say a 16' aluminum boat has a surface area of 16' x roughly 4' = 64' square feet or 9,216 sq. in.  500 gallons is equivalent to 231 cubic in. x 500 = 115,500 cubic in. of water divided by 9,216 sq. in. = 12" of rain per hour, for 4 hours. This would be a substantial amount of rain!

How to verify that your Sun Pump is working properly?
With the toggle switch in the "down" position, reach around to the bottom of the Sun Pump box and grasp the protruding blue knob with your thumb and index finger. Rotate the knob counter clockwise. You should hear a click and then the bilge pump will turn on. Release the knob, it should rotate clockwise and shut the bilge pump off, provided there isn't enough water in your boat to keep it activated.

If the float switch doesn't rotate counter clockwise enough to hear the switch click "on", insert your index finger into hole above the blue knob and push foam bulkhead up. Repeat knob rotation to confirm "on" and "off" operation. 

Procedure to check the charge status of your battery.
Occasionally, your battery may run down to a point that it will not activate the bilge pump. This may have been caused by small debris entering into the Sun Pump box and interfering with the action of the float switch, forcing it to remain on. First of all, verify the action of the float switch by rotating counterclockwise, the protruding blue knob. If the float switch activates "on" and "off" with audible clicking sounds, then your battery could may have been run down. First of all, make sure that your toggle switch is in the down position and then leave your Sun Pump in a bright location for a full day. After a full day, a very simple test is to just switch the toggle to the "up" position and it should activate the bilge pump. If it does, leave the pump in the sun for another full day. You can also test the battery using a 12 volt circuit tester or a small volt meter. 

 

Procedure to check the activation of your switch.
Not very often but sometimes, the toggle switch will fail. It will either work in the "up" Manual position or in the "down" Auto position or sometimes not at all. The easiest way to test the functionality of the switch is to by-pass it with a Jumper which can easily be fabricated from a large paper clip. Just bend it into a C shape and then open the lid of your Sun Pump. 12V power goes into the middle of the switch so if you touch one end of the paperclip on the middle tab of the back of the toggle switch and then alternatively touch the upper and lower tabs, you should hear the bilge pump turn on. Remember, with the lid upside down, the lower tab is the Auto position so you will also have to rotate the float switch via the blue projecting knob to activate the bilge pump.

  

Procedure to clean out your bilge pump.
When it is time to pull your boat from the water for the winter, it is a good idea to clean out your Sun Pump before you put it away. A simple garden hose spray through the bottom vents and access holes will wash out any accumulated grime and grunge. It is important to make sure that there isn't anything under the float switch so spray into this area and then activate the protruding knob. If there appears to be a bunch of debris around the basket of the bilge pump, you might want to pop the pump off the basket and wash this area out as well. Open the lid, remove the foam bulkhead, depress the tab on the basket with one hand, push down and twist the bilge pump counter clockwise. With your free hand, after the pump has started to rotate, make sure the outlet clears the pump box wall and it will twist and lift out free. Re-assemble after cleaning. 

  

Procedure to switch out your float switch.
Occassionally, the Attwood float switch fails and no longer activates the bilge pump. This may be due to weathering, continuous submersion in water or material degradation. To switch out the float switch, open the lid, remove the foam bulkhead and battery, turn over the pump box bottom, loosen the two screws. They only need to be loosened enough to disengage from the small nuts that hold the float switch in place. With wire cutters, cut the switch wires. With a replacement float switch, either solder and heat shrink the new float switch wires to the new ones after stripping the wire coating. The other option is to use crimp connectors, joining wire to wire. Pop out the nuts from the old float switch and place them into the little feet on either side of the float switch. Replace the float switch in the bottom of the pump, lining up the nuts with the screws. Gently tighten the screws, they should engage the nuts to hold the float switch in place. Re-assemble the Sun Pump and test before using.

  

How long should a Sun Pump battery last?
12 Volt Sealed Lead Acid batteries generally last at least 2 seasons and sometimes, up to 10 seasons. It really depends on the frequency of pumping during the seasons and the amount of direct sunlight the solar panel receives during the day. It is important to store your Sun Pump in a spot that receives some natural sunlight during the winter. The trickle charge from the solar panel will keep the battery stimulated.

Where can I get a replacement battery?
Replacement 12 volt 7 amp/hour gel cel batteries with F1 connectors are available at the following locations:

On our website - 12 volt replacement battery - or

For Canadian customers - Canadian Tire - batteries or

For American customers - Home Depot - batteries.

How high can a Sun Pump pump?
The maximum height a Sun Pump can pump is 10' high. At this height, there isn't much flow so I generally recommend that 3' is the maximum as that is the length of the hose that is included with the pump. If you want to pump out to a higher level, you will need an extra long piece of 3/4" bilge hose.

When you are finished with your Sun Pump.
If your trusty Sun Pump no longer has a boat to sit in and you haven't been able to give it away, Contact Us and we will find a home for it. The pumps can be refurbished and re-issued to other boaters. We are working on a bilge pump program for one of our local summer camps and they would appreciate the donation.