{"id":15109,"date":"2025-08-15T10:02:43","date_gmt":"2025-08-15T10:02:43","guid":{"rendered":"https:\/\/krogragg.com\/?p=15109"},"modified":"2025-08-15T10:02:43","modified_gmt":"2025-08-15T10:02:43","slug":"how-to-install-an-automatic-bilge-pump","status":"publish","type":"post","link":"https:\/\/krogragg.com\/?p=15109","title":{"rendered":"How to Install an Automatic Bilge Pump"},"content":{"rendered":"<p>    How to Install an Automatic Bilge Pump<br \/>\n \t<BR><br \/>\n<BR><\/BR><br \/>\n    <!-- no image --><br \/>\n \t<BR><br \/>\n<BR><\/BR><\/p>\n<div>\n<section class=\"hydra-container\">\n<div class=\"hydra-canvas\">\n\t\t\t\t\t<img data-recalc-dims=\"1\" fetchpriority=\"high\" decoding=\"async\" width=\"800\" height=\"600\" src=\"https:\/\/i0.wp.com\/boatingmag.com\/wp-content\/uploads\/2025\/07\/BTG725-WWK-Auto-Bilge-Pump-1-1024x768.jpg?resize=800%2C600&#038;ssl=1\" class=\"hydra-image disable-lazyload\" alt=\"Installing an automatic bilge pump\" sizes=\"(max-width: 1400px) 100vw, 1400px\" srcset=\"https:\/\/boatingmag.com\/wp-content\/uploads\/2025\/07\/BTG725-WWK-Auto-Bilge-Pump-1-1024x768.jpg 1024w, https:\/\/boatingmag.com\/wp-content\/uploads\/2025\/07\/BTG725-WWK-Auto-Bilge-Pump-1-300x225.jpg 300w, https:\/\/boatingmag.com\/wp-content\/uploads\/2025\/07\/BTG725-WWK-Auto-Bilge-Pump-1-768x576.jpg 768w, https:\/\/boatingmag.com\/wp-content\/uploads\/2025\/07\/BTG725-WWK-Auto-Bilge-Pump-1-1536x1151.jpg 1536w, https:\/\/boatingmag.com\/wp-content\/uploads\/2025\/07\/BTG725-WWK-Auto-Bilge-Pump-1.jpg 1945w\">                <\/div><figcaption class=\"caption margin_top_xs full border_1 hydra-figcaption\">\n                <span class=\"hydra-image-caption\">Select a pump with the same output or greater than the original pump.<\/span><br \/>\n                <span class=\"article_image_credit italic margin_right_xs\">Jim Hatch<\/span><\/p>\n<\/figcaption><\/section>\n<p><iframe id=\"wxuzj5efbz\" src=\"https:\/\/boatingmag.dragonforms.com\/wxuzj5efbz\" scrolling=\"no\" style=\"width:100%;height:165px;border:none;overflow:hidden;\"><\/iframe><\/p>\n<p>A dewatering device is strongly recommended by the US Coast Guard aboard boats, and electric bilge pumps fulfill this role. However, bilge pumps can wear out. Replacing the old pump with one that has a built-in automatic switch simplifies the installation by eliminating the need to mount and connect a separate automatic switch.\u00a0<\/p>\n<p>A number of models feature built-in switches that sense high bilge water and automatically begin dewatering. Attwood Marine, Johnson Pumps, Rule Industries, T-H Marine, and others offer automatic bilge pumps of various sizes and outputs, as measured in gallons per hour.<\/p>\n<p>Select a pump with the same output or greater than the original pump (see the chart below). For more on bilge-pump output, visit <a href=\"https:\/\/www.boatingmag.com\/choosing-right-bilge-pump\">boatingmag.com\/choosing-right-bilge-pump<\/a>. This project assumes that the boat already has a discharge hose leading to a through-hull fitting that is at least 8 inches above the heeled waterline.<\/p>\n<figure class=\"wp-block-table\">\n<table class=\"has-fixed-layout\">\n<tbody>\n<tr>\n<td><strong>Less than 18 feet:<\/strong><\/td>\n<td>1,000 gph<\/td>\n<\/tr>\n<tr>\n<td><strong>18 to 25 feet:<\/strong><\/td>\n<td>2,500 gph<\/td>\n<\/tr>\n<tr>\n<td><strong>25 to 32 feet:<\/strong><\/td>\n<td>4,000 gph<\/td>\n<\/tr>\n<tr>\n<td><strong>32 to 36 feet:<\/strong><\/td>\n<td>6,000 gph<\/td>\n<\/tr>\n<tr>\n<td><strong>36 to 45 feet:<\/strong><\/td>\n<td>8,500 gph<\/td>\n<\/tr>\n<\/tbody>\n<\/table><figcaption class=\"wp-element-caption\">Here are rules of thumb for deciding on the best bilge-pump output based on boatlength. If in doubt, err on the side of greater output.<\/figcaption><\/figure>\n<p>Your bilge-pump system should have a dedicated switch. If your boat doesn\u2019t have one, stand-alone switches are available from the same brands that offer automatic bilge pumps.<\/p>\n<p>For this installation aboard a 17-foot flats skiff, we chose to retrofit with the Rule-Mate 1100 automatic bilge pump (1,122 gph). This 12-volt DC pump kicks into gear when bilge water reaches 2\u00a0inches and shuts down at 3\/8\u00a0inch.\u00a0It has a check valve to prevent backflow of water. We matched it with a Rule Model\u00a043 three-way lighted \u00adrocker-panel bilge-pump switch.<\/p>\n<p><strong>Skill Level:<\/strong> 1 of 5<\/p>\n<p><strong>Finish Time:<\/strong> Approx. 2-3 hours<\/p>\n<h2 class=\"wp-block-heading\">Tools and Supplies<\/h2>\n<ul class=\"wp-block-list\">\n<li>\n<a href=\"https:\/\/outclick.co\/l\/01k19awcxyr3vabwz94ryat368\" target=\"_blank\" rel=\"noreferrer noopener nofollow\">Rule-Mate 1100<\/a> automatic bilge pump (<a href=\"https:\/\/outclick.co\/l\/01k19awcxyr3vabwz94ryat368\" target=\"_blank\" rel=\"noreferrer noopener nofollow\">westmarine.com<\/a>)\u00a0<\/li>\n<li>Rule three-way lighted \u00adrocker-panel <a href=\"https:\/\/outclick.co\/l\/01k19az3wc0bjh97b1f89yxcrf\" target=\"_blank\" rel=\"noreferrer noopener nofollow\">bilge-pump switch<\/a>, Model 43 (<a href=\"https:\/\/outclick.co\/l\/01k19az3wc0bjh97b1f89yxcrf\" target=\"_blank\" rel=\"noreferrer noopener nofollow\">amazon.com<\/a>)<\/li>\n<li>1-inch ID flexible hose (if \u00adreplacing the discharge line)<\/li>\n<li>Two stainless-steel hose clamps\u00a0<\/li>\n<li>\n<a href=\"https:\/\/outclick.co\/l\/01jd5chj1ykpkmpvv568z84s7m\" target=\"_blank\" rel=\"noreferrer noopener nofollow\">Power drill<\/a> and bit set<\/li>\n<li>\n<a href=\"https:\/\/outclick.co\/l\/01jtr0yz0c7t64h7y50pa0jhra\" target=\"_blank\" rel=\"noreferrer noopener nofollow\">Jig saw<\/a> or coping saw<\/li>\n<li><a href=\"https:\/\/outclick.co\/l\/01k19b8wgtz69d5m7d6zghmeyp\" target=\"_blank\" rel=\"noreferrer noopener nofollow\">Phillips screwdriver<\/a><\/li>\n<li>Slotted screwdriver or <a href=\"https:\/\/outclick.co\/l\/01k19bdw7jszgr4dx5qvvw4mpz\" target=\"_blank\" rel=\"noreferrer noopener nofollow\">hex driver<\/a> (for hose clamps)<\/li>\n<li>Various crimp connectors with heat-shrink collars<\/li>\n<li>\n<a href=\"https:\/\/outclick.co\/l\/01jaaka9a5c4p0ecj8gmk3q8hg\" target=\"_blank\" rel=\"noreferrer noopener nofollow\">Wire strippers<\/a> and \u00adcrimping\u00a0tool<\/li>\n<li>\n<a href=\"https:\/\/outclick.co\/l\/01jmdb5zxzfxmmm6863932hn4s\" target=\"_blank\" rel=\"noreferrer noopener nofollow\">Heat gun<\/a>\u00a0<\/li>\n<li>Zip ties to support wires\u00a0<\/li>\n<li><a href=\"https:\/\/outclick.co\/l\/01k0sbs138wahwszkms4d51ev3\" target=\"_blank\" rel=\"noreferrer noopener nofollow\">Marine silicone sealant<\/a><\/li>\n<li>Shop rags (to wipe away excess sealant)<\/li>\n<\/ul>\n<section class=\"hydra-container\">\n<div class=\"hydra-canvas\">\n\t\t\t\t\t<img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"800\" height=\"600\" src=\"https:\/\/i0.wp.com\/boatingmag.com\/wp-content\/uploads\/2025\/07\/BTG725-WWK-Auto-Bilge-Pump-2.jpg?resize=800%2C600&#038;ssl=1\" class=\"hydra-image\" alt=\"Choose the pump location\" sizes=\"(max-width: 1400px) 100vw, 1400px\" srcset=\"https:\/\/boatingmag.com\/wp-content\/uploads\/2025\/07\/BTG725-WWK-Auto-Bilge-Pump-2.jpg 1009w, https:\/\/boatingmag.com\/wp-content\/uploads\/2025\/07\/BTG725-WWK-Auto-Bilge-Pump-2-300x225.jpg 300w, https:\/\/boatingmag.com\/wp-content\/uploads\/2025\/07\/BTG725-WWK-Auto-Bilge-Pump-2-768x576.jpg 768w\">                <\/div><figcaption class=\"caption margin_top_xs full border_1 hydra-figcaption\">\n                <span class=\"hydra-image-caption\">When choosing a location it\u2019s important to have easy access for maintenance.<\/span><br \/>\n                <span class=\"article_image_credit italic margin_right_xs\">Jim Hatch<\/span><\/p>\n<\/figcaption><\/section>\n<h2 class=\"wp-block-heading\">Select a Location<\/h2>\n<p>It often proves easiest to use the same location as the previous bilge pump, which is usually near the stern of the boat and as deep in the bilge as is practicable. Just as important is access for installation and cleaning the pump grate (and removing the check valve during the winterization process). There is often a hatch or deck plate above the pump for this purpose. Many boats have pads \u2019glassed onto the hull interior. This elevates the pump a bit so that it\u2019s not running continuously from residual bilge water, and gives you a place to fasten the pump without drilling into the hull proper.<\/p>\n<p><strong>Tip:<\/strong> When selecting a bilge pump, take into account \u201clift\u201d\u2014the vertical distance a pump must raise water to reach the discharge fitting. Lift reduces the rated output. With the Rule-Mate 1100, for example, a 3.3-foot lift cuts the output to 792 gph; a 6.7-foot lift cuts output to 456 gph.<\/p>\n<section class=\"hydra-container\">\n<div class=\"hydra-canvas\">\n\t\t\t\t\t<img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"800\" height=\"600\" src=\"https:\/\/i0.wp.com\/boatingmag.com\/wp-content\/uploads\/2025\/07\/BTG725-WWK-Auto-Bilge-Pump-3-1024x768.jpg?resize=800%2C600&#038;ssl=1\" class=\"hydra-image\" alt=\"Install the pump\" sizes=\"(max-width: 1400px) 100vw, 1400px\" srcset=\"https:\/\/boatingmag.com\/wp-content\/uploads\/2025\/07\/BTG725-WWK-Auto-Bilge-Pump-3-1024x768.jpg 1024w, https:\/\/boatingmag.com\/wp-content\/uploads\/2025\/07\/BTG725-WWK-Auto-Bilge-Pump-3-300x225.jpg 300w, https:\/\/boatingmag.com\/wp-content\/uploads\/2025\/07\/BTG725-WWK-Auto-Bilge-Pump-3-768x576.jpg 768w, https:\/\/boatingmag.com\/wp-content\/uploads\/2025\/07\/BTG725-WWK-Auto-Bilge-Pump-3-1536x1152.jpg 1536w, https:\/\/boatingmag.com\/wp-content\/uploads\/2025\/07\/BTG725-WWK-Auto-Bilge-Pump-3.jpg 1814w\">                <\/div><figcaption class=\"caption margin_top_xs full border_1 hydra-figcaption\">\n                <span class=\"hydra-image-caption\">Use the base as a template to mark two holes for drilling.<\/span><br \/>\n                <span class=\"article_image_credit italic margin_right_xs\">Jim Hatch<\/span><\/p>\n<\/figcaption><\/section>\n<h2 class=\"wp-block-heading\">Install the Pump<\/h2>\n<p>Detach the base grate from the pump by pressing on the two tabs. Then use the base as a template to mark two holes, ensuring that the pump will be oriented so that the discharge hose can be easily attached to the outlet. Drill the two holes with a <sup>1<\/sup>\u2044<sub>8<\/sub>-inch bit in the mounting pad, taking care not to drill through too far. Dab each hole with marine sealant, and drive in No. 8 self-tapping stainless-steel screws of appropriate length to secure the pump but not penetrate the hull. Attach the outlet hose with two stainless-steel hose clamps to the pump fitting, and snap the\u00a0pump\u00a0into position.\u00a0<\/p>\n<p><strong>Tip:<\/strong> If you need to replace the discharge hose, know that smoothbore marine hose offers less resistance to water flow than does corrugated hose, thus improving efficiency in removing bilge water. If possible, choose flexible smoothbore marine hose or sanitation hose.\u00a0<\/p>\n<section class=\"hydra-container\">\n<div class=\"hydra-canvas\">\n\t\t\t\t\t<img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"800\" height=\"600\" src=\"https:\/\/i0.wp.com\/boatingmag.com\/wp-content\/uploads\/2025\/07\/BTG725-WWK-Auto-Bilge-Pump-4-1024x768.jpg?resize=800%2C600&#038;ssl=1\" class=\"hydra-image\" alt=\"Install the switch\" sizes=\"(max-width: 1400px) 100vw, 1400px\" srcset=\"https:\/\/boatingmag.com\/wp-content\/uploads\/2025\/07\/BTG725-WWK-Auto-Bilge-Pump-4-1024x768.jpg 1024w, https:\/\/boatingmag.com\/wp-content\/uploads\/2025\/07\/BTG725-WWK-Auto-Bilge-Pump-4-300x225.jpg 300w, https:\/\/boatingmag.com\/wp-content\/uploads\/2025\/07\/BTG725-WWK-Auto-Bilge-Pump-4-768x576.jpg 768w, https:\/\/boatingmag.com\/wp-content\/uploads\/2025\/07\/BTG725-WWK-Auto-Bilge-Pump-4-1536x1152.jpg 1536w, https:\/\/boatingmag.com\/wp-content\/uploads\/2025\/07\/BTG725-WWK-Auto-Bilge-Pump-4.jpg 1833w\">                <\/div><figcaption class=\"caption margin_top_xs full border_1 hydra-figcaption\">\n                <span class=\"hydra-image-caption\">Use a jigsaw to create a cutout for the bilge pump switch.<\/span><br \/>\n                <span class=\"article_image_credit italic margin_right_xs\">Jim Hatch<\/span><\/p>\n<\/figcaption><\/section>\n<h2 class=\"wp-block-heading\">Install the Switch<\/h2>\n<p>Using a jig saw, carefully create a 2 <sup>5<\/sup> \u2044<sub>16<\/sub>-inch-wide-by-\u00ad\u200b1 <sup>11<\/sup> \u2044<sub>16<\/sub>-inch-tall cutout in an accessible location on the dash. Insert the 2 <sup>7<\/sup>\u2044<sub>8<\/sub>-inch-wide-by-2 <sup>3<\/sup>\u2044<sub>8<\/sub>-inch-tall switch panel into the cutout and mark the four mounting holes, ensuring that the panel is aligned as you wish. Remove the panel and drill the four holes with a <sup>1<\/sup>\u2044<sub>8<\/sub>-inch drill bit, then slightly chamfer them with a countersink bit to prevent chipping when driving in the fasteners. Place the panel in the cutout, dab each hole with marine sealant, and then carefully drive in the supplied No. 8 flat-head self-tapping screws. Do not overtighten.\u00a0<\/p>\n<p><strong>Tip:<\/strong> The Rule switch requires adding a glass\u00a0fuse through a twist-and-lock port\u00a0on the face of the panel. Refer to\u00a0the chart in the instruction manual to determine the amperage for the fuse based on\u00a0the length and gauge of the wire run between the switch and the pump.<\/p>\n<section class=\"hydra-container\">\n<div class=\"hydra-canvas\">\n\t\t\t\t\t<img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"800\" height=\"600\" src=\"https:\/\/i0.wp.com\/boatingmag.com\/wp-content\/uploads\/2025\/07\/BTG725-WWK-Auto-Bilge-Pump-5.jpg?resize=800%2C600&#038;ssl=1\" class=\"hydra-image\" alt=\"Run the wires\" sizes=\"(max-width: 1400px) 100vw, 1400px\" srcset=\"https:\/\/boatingmag.com\/wp-content\/uploads\/2025\/07\/BTG725-WWK-Auto-Bilge-Pump-5.jpg 1000w, https:\/\/boatingmag.com\/wp-content\/uploads\/2025\/07\/BTG725-WWK-Auto-Bilge-Pump-5-300x225.jpg 300w, https:\/\/boatingmag.com\/wp-content\/uploads\/2025\/07\/BTG725-WWK-Auto-Bilge-Pump-5-768x576.jpg 768w\">                <\/div><figcaption class=\"caption margin_top_xs full border_1 hydra-figcaption\">\n                <span class=\"hydra-image-caption\">Ensure that all wires are supported and don\u2019t sag into any bilge\u00a0water.<\/span><br \/>\n                <span class=\"article_image_credit italic margin_right_xs\">Jim Hatch<\/span><\/p>\n<\/figcaption><\/section>\n<h2 class=\"wp-block-heading\">Run the Wires<\/h2>\n<p>The \u00adRule-Mate pump has three wires, and you will need to add extensions to at least two. Use crimp-on butt connectors with heat-shrink collars to create corrosion-resistant connections. Choose the gauge wire for the run based on the chart provided in the instruction manual. Run the\u00a0brown and brown\/white wires to the switch at the helm. Run the black wire to the ground circuit. You will also need to run a separate positive wire (hot line) directly from the positive terminal of the battery to the\u00a0switch at the\u00a0helm. Ensure that all wires are supported and don\u2019t sag into any bilge\u00a0water.<\/p>\n<section class=\"hydra-container\">\n<div class=\"hydra-canvas\">\n\t\t\t\t\t<img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"800\" height=\"600\" src=\"https:\/\/i0.wp.com\/boatingmag.com\/wp-content\/uploads\/2025\/07\/BTG725-WWK-Auto-Bilge-Pump-6-1024x768.jpg?resize=800%2C600&#038;ssl=1\" class=\"hydra-image\" alt=\"Making the connections\" sizes=\"(max-width: 1400px) 100vw, 1400px\" srcset=\"https:\/\/boatingmag.com\/wp-content\/uploads\/2025\/07\/BTG725-WWK-Auto-Bilge-Pump-6-1024x768.jpg 1024w, https:\/\/boatingmag.com\/wp-content\/uploads\/2025\/07\/BTG725-WWK-Auto-Bilge-Pump-6-300x225.jpg 300w, https:\/\/boatingmag.com\/wp-content\/uploads\/2025\/07\/BTG725-WWK-Auto-Bilge-Pump-6-768x576.jpg 768w, https:\/\/boatingmag.com\/wp-content\/uploads\/2025\/07\/BTG725-WWK-Auto-Bilge-Pump-6-1536x1152.jpg 1536w, https:\/\/boatingmag.com\/wp-content\/uploads\/2025\/07\/BTG725-WWK-Auto-Bilge-Pump-6.jpg 2000w\">                <\/div><figcaption class=\"caption margin_top_xs full border_1 hydra-figcaption\">\n                <span class=\"hydra-image-caption\">Crimp on the supplied female spade connectors, and connect them to the male spade connectors on the back of the switch.<\/span><br \/>\n                <span class=\"article_image_credit italic margin_right_xs\">Jim Hatch<\/span><\/p>\n<\/figcaption><\/section>\n<h2 class=\"wp-block-heading\">Make the Connections<\/h2>\n<p>Crimp on the supplied female spade connectors to the brown, brown\/white and hot line, and connect them to the male spade connectors on the back of the switch as follows: brown to auto function, brown\/white to manual override function, and hot line to the open spade connector at the back of the fuse port. Connect the spade connector for ground function on the switch to the ground circuit with a black wire. Crimp on ring connectors to the opposite end of the hot line and black wire, and connect to the positive terminal of the battery and ground circuit, respectively.<\/p>\n<h2 class=\"wp-block-heading\">Testing the System\u00a0<\/h2>\n<p>To test the Rule-Mate automatic-bilge-pump system, press down the momentary switch at the bottom of the rocker and listen for the whirring of the pump, indicating that the manual override function is working. Next press the latching switch at the top of the rocker. An indicator light confirms that power is getting to the pump. Then touch the Pumpcheck button on the pump itself on the opposite side of the outlet, hold your finger there for 5 seconds, and listen for the pump to begin running, indicating that the automatic function is also working.\u00a0<\/p>\n<p>The post <a rel=\"nofollow\" href=\"https:\/\/boatingmag.com\/how-to\/installing-an-automatic-bilge-pump\/\">How to Install an Automatic Bilge Pump<\/a> appeared first on <a rel=\"nofollow\" href=\"https:\/\/boatingmag.com\/\">Boating Mag<\/a>.<\/p>\n<\/div>\n<p> \t<BR><br \/>\n <BR><\/BR><br \/>\n    Jim Hendricks<br \/>\n \t<BR><br \/>\n<BR><\/BR><br \/>\n<a href=\"https:\/\/boatingmag.com\/how-to\/installing-an-automatic-bilge-pump\/\">Go to boatingmag<\/a><br \/>\n \t<BR><br \/>\n <BR><\/BR><\/p>\n","protected":false},"excerpt":{"rendered":"<p>How to Install an Automatic Bilge Pump Select a pump with the same output or greater than the original pump. Jim Hatch A dewatering device is strongly recommended by the US Coast Guard aboard boats, and electric bilge pumps fulfill this role. However, bilge pumps can wear out. Replacing the old pump with one that [&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[176,5157,126,179,175,181],"tags":[127],"class_list":["post-15109","post","type-post","status-publish","format-standard","hentry","category-affiliate","category-august-september-2025","category-boatingmag","category-diy-projects","category-how-to","category-weekend-workbook","tag-boatingmag"],"_links":{"self":[{"href":"https:\/\/krogragg.com\/index.php?rest_route=\/wp\/v2\/posts\/15109"}],"collection":[{"href":"https:\/\/krogragg.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/krogragg.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/krogragg.com\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/krogragg.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=15109"}],"version-history":[{"count":0,"href":"https:\/\/krogragg.com\/index.php?rest_route=\/wp\/v2\/posts\/15109\/revisions"}],"wp:attachment":[{"href":"https:\/\/krogragg.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=15109"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/krogragg.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=15109"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/krogragg.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=15109"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}