{"product_id":"centek-exhaust-thru-hull-4in-flapper-1200326-white","title":"Centek 4 in. Exhaust Thru-Hull with Flapper 1200326 | White","description":"\u003ch2\u003eCentek 4 in. Exhaust Thru-Hull with Flapper 1200326\u003c\/h2\u003e\n\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003ePart Number:\u003c\/strong\u003e 1200326 (Centek Marine)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Centek Marine\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProduct Type:\u003c\/strong\u003e Marine Exhaust Thru-Hull with Flapper\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eColor:\u003c\/strong\u003e White\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eExhaust Hose Size:\u003c\/strong\u003e 4 in. \/ 102 mm ID\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eConstruction:\u003c\/strong\u003e Compression-molded fiberglass \/ fiberglass-reinforced resin\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUPC:\u003c\/strong\u003e 808880120487\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eCentek 1200326 is a white compression-molded fiberglass marine exhaust thru-hull fitting for wet-exhaust systems using 4 in. \/ 102 mm inside-diameter exhaust hose. It installs through the transom or hull side at the exhaust discharge point, with the hose connecting to the inside shank and the flange and weighted rubber flapper remaining on the exterior. The external rubber flapper reduces backflow of water through the exhaust outlet when the boat is stopped, moving slowly, or backing down.\u003c\/p\u003e\n\n\u003ch2\u003eDimensions\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eExhaust Hose Size:\u003c\/strong\u003e 4 in. \/ 102 mm\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFlange Outside Diameter:\u003c\/strong\u003e 6.00 in. \/ 152 mm\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOverall Length:\u003c\/strong\u003e 7.75 in. \/ 197 mm\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThru-Hull \/ Shank Length:\u003c\/strong\u003e 4.50 in. \/ 114 mm\u003c\/li\u003e\n\u003cli\u003eWeighted external rubber flapper\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eCompatible Applications\u003c\/h2\u003e\n\u003cp\u003eSuitable for:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eMarine wet-exhaust systems requiring a 4 in. \/ 102 mm exhaust hose connection\u003c\/li\u003e\n\u003cli\u003eTransom or hull-side exhaust discharge installations\u003c\/li\u003e\n\u003cli\u003eNew builds and exhaust-system replacements where a 6.00 in. \/ 152 mm exterior flange fits the mounting area\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eConfirm exhaust hose inside diameter, available hull or transom thickness, required flange diameter, and clearance for the external flapper before ordering.\u003c\/p\u003e\n\n\u003ch2\u003eReplacement Flapper\u003c\/h2\u003e\n\u003cp\u003eThe external rubber flapper is serviceable separately. If the thru-hull body remains structurally sound, the flapper can be replaced without replacing the entire fitting using Centek repair kit \u003cstrong\u003e1200340\u003c\/strong\u003e, which includes a rubber flapper, two mounting screws, and a retaining plate.\u003c\/p\u003e\n\n\u003ch2\u003eRelated Part Numbers\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eCentek:\u003c\/strong\u003e 1200326 (this part — white, with flapper)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDistributor\/Catalogue Reference:\u003c\/strong\u003e 383-1200326\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBlack equivalent with flapper:\u003c\/strong\u003e Centek 1200325\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWhite version without flapper:\u003c\/strong\u003e Centek 1200324\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eReplacement 4 in. flapper repair kit:\u003c\/strong\u003e Centek 1200340\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eWhen to Replace the Thru-Hull\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eFiberglass body is cracked or structurally compromised\u003c\/li\u003e\n\u003cli\u003eHose-connection shank is damaged or deformed\u003c\/li\u003e\n\u003cli\u003eMounting flange or holes are deteriorated\u003c\/li\u003e\n\u003cli\u003eExhaust or cooling water leaks around the fitting\u003c\/li\u003e\n\u003cli\u003eFitting is being replaced as part of a full exhaust-system rebuild\u003c\/li\u003e\n\u003cli\u003eFlapper mounting area is damaged beyond serviceability\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eIf only the flapper shows wear, the flapper can be replaced separately using Centek 1200340 — a full thru-hull replacement is not required.\u003c\/p\u003e\n\n\u003ch2\u003eInstallation Notes\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eConfirm the hull opening and mounting area suit the 6.00 in. \/ 152 mm exterior flange\u003c\/li\u003e\n\u003cli\u003eEnsure the mating hull or transom surface is clean and flat before fitting\u003c\/li\u003e\n\u003cli\u003eApply a marine-grade sealant around the flange for a watertight installation\u003c\/li\u003e\n\u003cli\u003eUse 4 in. \/ 102 mm ID marine exhaust hose on the interior connection\u003c\/li\u003e\n\u003cli\u003eTighten all mounting hardware evenly — do not overtighten on the fiberglass flange\u003c\/li\u003e\n\u003cli\u003eAvoid excessive hose-clamp pressure on the fiberglass shank\u003c\/li\u003e\n\u003cli\u003eConfirm the flapper opens freely and swings clear of the hull after installation\u003c\/li\u003e\n\u003cli\u003eInspect for exhaust and cooling-water leaks after startup\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eParts Desk Insights\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003eBest use case:\u003c\/strong\u003e Centek 1200326 is the right choice for any wet-exhaust system running 4 in. exhaust hose where a white fiberglass outlet is preferred — common on vessels with white transoms or hulls where a black fitting would stand out. The compression-molded fiberglass body resists the corrosion that affects metallic exhaust fittings over time, and the weighted external flapper is effective at reducing water ingestion when the boat is stopped or backing down.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eCommon issue:\u003c\/strong\u003e The most frequent ordering error is not confirming the exterior flange diameter before purchasing. At 6.00 in. \/ 152 mm, the flange is significantly larger than the 4 in. hose connection — the available mounting area on the transom needs to be verified before ordering. Customers also sometimes replace the complete thru-hull when only the rubber flapper has failed; the Centek 1200340 flapper repair kit is the more economical fix when the fiberglass body is still in good condition. Also confirm whether a flapper is needed at all — Centek 1200324 is the white 4 in. version without a flapper, suited for applications where the flapper is not required or is undesirable.\u003c\/p\u003e\n\u003cp\u003eShop all exhaust components in our \u003ca href=\"\/collections\/exhaust-systems\"\u003eExhaust Systems\u003c\/a\u003e collection or browse \u003ca href=\"\/collections\/engine-parts-maintenance\"\u003eEngine Parts \u0026amp; Maintenance\u003c\/a\u003e for related components.\u003c\/p\u003e","brand":"LNS","offers":[{"title":"Default Title","offer_id":51156126531620,"sku":"383-1200326","price":299.79,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0743\/5799\/7604\/files\/383-1200298.jpg?v=1784926240","url":"https:\/\/marisolmarine.com\/products\/centek-exhaust-thru-hull-4in-flapper-1200326-white","provider":"Marisol Marine Company","version":"1.0","type":"link"}