{"product_id":"sierra-exhaust-manifold-riser-18-1907-3in","title":"Sierra Exhaust Manifold Riser 18-1907 | 3 in. \/ 76.2 mm Outlet","description":"\u003ch2\u003eSierra Exhaust Manifold Riser 18-1907\u003c\/h2\u003e\n\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003ePart Number:\u003c\/strong\u003e 18-1907 (Sierra)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Sierra\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProduct Type:\u003c\/strong\u003e Exhaust Manifold Riser \/ Elbow\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eExhaust Outlet:\u003c\/strong\u003e 3 in. \/ 76.2 mm\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eApplication:\u003c\/strong\u003e Marine inboard and sterndrive center-riser exhaust systems\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUPC:\u003c\/strong\u003e 808282127411\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eSierra 18-1907 is a cast marine exhaust manifold riser \/ elbow for selected center-riser exhaust manifold systems on inboard and sterndrive gasoline engines. It routes exhaust gases and engine cooling water from the exhaust manifold into the downstream marine exhaust hose. Sierra lists 18-1907 for direct use with manifolds 18-1997-1 and 18-1998-1. All Sierra exhaust risers are painted, packaged, and leak-tested before shipment.\u003c\/p\u003e\n\n\u003ch2\u003eCompatible Applications\u003c\/h2\u003e\n\u003cp\u003eDocumented engine families and manifold systems:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eFord 302 CID \/ 4.9L V8 — marine inboard applications\u003c\/li\u003e\n\u003cli\u003eFord 351 CID \/ 5.8L V8 — marine inboard applications\u003c\/li\u003e\n\u003cli\u003eSelected GM-based marine engines (283, 305, 307, 327, 350 CID) when paired with compatible center-riser manifold configurations\u003c\/li\u003e\n\u003cli\u003eFor use with Sierra exhaust manifold 18-1997-1 or 18-1998-1\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eAlways confirm the existing exhaust manifold part number, riser part number, exhaust outlet diameter, and cooling-water gasket configuration before ordering. Exhaust riser fitment depends on the manifold and gasket arrangement, not engine displacement alone.\u003c\/p\u003e\n\n\u003ch2\u003eCompatible Gaskets \u0026amp; Mounting Hardware\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eOpen riser gasket — Sierra 18-2854\u003c\/li\u003e\n\u003cli\u003eBlocked riser gasket — Sierra 18-0476\u003c\/li\u003e\n\u003cli\u003eOpen mounting kit — Sierra 18-4364\u003c\/li\u003e\n\u003cli\u003eBlocked mounting kit — Sierra 18-8535\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eThe correct gasket type (open vs. blocked) depends on your engine’s cooling-system configuration. Confirm this before ordering gaskets or hardware.\u003c\/p\u003e\n\n\u003ch2\u003eCross-Reference Part Numbers\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSierra:\u003c\/strong\u003e 18-1907\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSupplier\/Internal Reference:\u003c\/strong\u003e 47-1907\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBarr:\u003c\/strong\u003e 20-0102\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIndmar:\u003c\/strong\u003e 53-2009\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIndmar:\u003c\/strong\u003e 53-2018\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eWhen to Replace the Riser\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eInternal cooling-water passages are restricted by corrosion or scale\u003c\/li\u003e\n\u003cli\u003eRust scaling is visible inside the exhaust passage\u003c\/li\u003e\n\u003cli\u003eCooling water leaks externally at the riser or manifold joint\u003c\/li\u003e\n\u003cli\u003eWater intrusion is found near the manifold\/riser gasket surface\u003c\/li\u003e\n\u003cli\u003eThe casting is cracked or the outlet neck has deteriorated\u003c\/li\u003e\n\u003cli\u003eExhaust-system overheating has occurred\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eNote:\u003c\/strong\u003e Marine exhaust risers operate in a continuous mix of heat, exhaust gas, and cooling water. Internal deterioration often progresses well before significant exterior damage becomes visible. Inspect the internal passages any time the riser is removed.\u003c\/p\u003e\n\n\u003ch2\u003eInstallation Notes\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eInspect the manifold sealing surface thoroughly and remove all old gasket material\u003c\/li\u003e\n\u003cli\u003eDetermine whether your application requires an open or blocked riser gasket before ordering hardware\u003c\/li\u003e\n\u003cli\u003eInspect the manifold internally for corrosion before fitting the new riser\u003c\/li\u003e\n\u003cli\u003eReplace corroded mounting fasteners rather than reusing them\u003c\/li\u003e\n\u003cli\u003eTorque all fasteners to the engine or manifold manufacturer’s specification\u003c\/li\u003e\n\u003cli\u003eInspect the 3 in. \/ 76.2 mm exhaust hose, bellows, and clamps during the same service\u003c\/li\u003e\n\u003cli\u003eCheck for exhaust and cooling-water leaks at startup before returning to service\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 Sierra 18-1907 is the right riser for any boat running Sierra exhaust manifolds 18-1997-1 or 18-1998-1, or engines cross-referencing Barr 20-0102 or Indmar 53-2009 \/ 53-2018. The 3 in. \/ 76.2 mm outlet and center-riser design make it a direct-fit replacement for scheduled exhaust system service — particularly on Ford 302 and 351 V8 marine applications and compatible GM-block installations using the same manifold family.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eCommon issue:\u003c\/strong\u003e The most frequent ordering mistake is selecting a riser by engine displacement without confirming the manifold part number and cooling-passage gasket type. Open and blocked cooling configurations use different gaskets that are not interchangeable — ordering the wrong gasket alongside an otherwise correct riser is a common service call. Always identify the manifold number and gasket configuration before completing the order. Internal riser corrosion is also frequently missed during visual inspection; always probe the internal passages before deciding whether a riser or a full manifold-and-riser replacement is needed.\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":51156127547428,"sku":"47-1907","price":427.59,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0743\/5799\/7604\/files\/47-1907.jpg?v=1784926269","url":"https:\/\/marisolmarine.com\/products\/sierra-exhaust-manifold-riser-18-1907-3in","provider":"Marisol Marine Company","version":"1.0","type":"link"}