{"product_id":"cylinder-head-hose-starboard-for-johnson-evinrude-90-115-hp-outboards-replaces-omc-340975-sierra-18-70936","title":"Sierra 18-70936 Starboard Cylinder Head Hose - Replaces OMC 340975, 321724, Fits 88-115 HP Outboards","description":"\u003cp\u003eThe Sierra 18-70936 is a starboard-side cylinder head hose engineered as a direct replacement for outboard engines that require this specific coolant hose. It routes coolant to and from the starboard cylinder head, and because it is a side-specific part, it is built to the exact length and routing needed for the starboard position only -- it is not interchangeable with the port-side hose. The hose is molded from silicone in white, a material chosen for its resistance to heat cycling, ozone, and the flexing that occurs as the engine runs and cools. Silicone construction helps the hose hold its shape and seal integrity over repeated thermal cycles, reducing the risk of cracking or coolant leaks that can occur with hoses made from lower-grade rubber compounds.\u003c\/p\u003e\u003cp\u003eThis hose is a direct cross-reference replacement for OMC part numbers 340975 and 321724, making it a straightforward swap for boat owners doing routine cooling-system maintenance or replacing a cracked, hardened, or leaking original hose. It fits a specific range of outboard horsepower and model designations as listed below. Buyers needing the matching port-side cylinder head hose should note that it is a separate part, Sierra 18-70937, since the two sides use different hose lengths and routing and are not interchangeable.\u003c\/p\u003e\u003ch3\u003eSpecifications\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Sierra\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Part Number:\u003c\/strong\u003e 18-70936\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProduct Type:\u003c\/strong\u003e Cylinder Head Hose\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSide:\u003c\/strong\u003e Starboard\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial:\u003c\/strong\u003e Silicone\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eColor:\u003c\/strong\u003e White\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight:\u003c\/strong\u003e 0.41 pounds\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUPC:\u003c\/strong\u003e 808282203375\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eFitment\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e90 HP (1994-95)\u003c\/li\u003e\n\u003cli\u003e100 HP (1996-97)\u003c\/li\u003e\n\u003cli\u003e115 HP (1994-97)\u003c\/li\u003e\n\u003cli\u003eE88 (1996)\u003c\/li\u003e\n\u003cli\u003eE90 (1996-98)\u003c\/li\u003e\n\u003cli\u003eE100 (1996-97)\u003c\/li\u003e\n\u003cli\u003eE112 (1996)\u003c\/li\u003e\n\u003cli\u003eE115 (1996-98)\u003c\/li\u003e\n\u003cli\u003eJ88 (1996)\u003c\/li\u003e\n\u003cli\u003eJ90 (1996-98)\u003c\/li\u003e\n\u003cli\u003eJ100 (1997-98)\u003c\/li\u003e\n\u003cli\u003eJ112 (1996)\u003c\/li\u003e\n\u003cli\u003eJ115 (1996-98)\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eReplaces (OEM)\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e340975\u003c\/li\u003e\n\u003cli\u003e321724\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\u003cp\u003e\u003cstrong\u003eIs the Sierra 18-70936 for the port or starboard side?\u003c\/strong\u003e The Sierra 18-70936 is the starboard cylinder head hose only. The matching port-side hose is a different part, Sierra 18-70937, so make sure you order the correct side for your engine.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat OEM part numbers does the 18-70936 replace?\u003c\/strong\u003e It replaces OMC 340975 and OMC 321724. If either number is stamped on your old hose, the Sierra 18-70936 is the correct cross-reference for the starboard side.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat outboard models and horsepower does this hose fit?\u003c\/strong\u003e The 18-70936 fits 90 HP (1994-95), 100 HP (1996-97), and 115 HP (1994-97) outboards, as well as the E88 (1996), E90 (1996-98), E100 (1996-97), E112 (1996), E115 (1996-98), J88 (1996), J90 (1996-98), J100 (1997-98), J112 (1996), and J115 (1996-98) model designations.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat material is the 18-70936 cylinder head hose made from?\u003c\/strong\u003e It is made from white silicone, chosen for its resistance to heat and ozone exposure and its ability to keep flexing without cracking through repeated engine heat cycles.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow much does the Sierra 18-70936 weigh?\u003c\/strong\u003e The hose weighs 0.41 pounds.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eCan I use the 18-70936 on the port-side cylinder head instead?\u003c\/strong\u003e No. The 18-70936 is molded and routed specifically for the starboard side. For the port side, use Sierra 18-70937, which is a separate part with its own routing and length.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs this a genuine OEM hose or an aftermarket replacement?\u003c\/strong\u003e The Sierra 18-70936 is an aftermarket replacement hose built as a direct cross-reference for OMC 340975 and 321724, not an OEM-branded part.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eDoes the 18-70936 come with clamps or fittings?\u003c\/strong\u003e The 18-70936 is the cylinder head hose itself; clamps and fittings are not included as part of this hose.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhy would I need to replace this hose?\u003c\/strong\u003e Cylinder head hoses harden, crack, or develop leaks over time from repeated heat cycling. If your starboard-side coolant hose shows cracking or is leaking, the 18-70936 is the direct replacement.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eDoes the UPC 808282203375 identify the Sierra 18-70936 hose?\u003c\/strong\u003e Yes, UPC 808282203375 corresponds to the Sierra 18-70936 starboard cylinder head hose.\u003c\/p\u003e","brand":"Sierra","offers":[{"title":"Default Title","offer_id":48988362768603,"sku":"SIE-18-70936","price":17.27,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0839\/7586\/4539\/files\/SIE-18-70936_lg__12594.1558130493.500.750.jpg?v=1785188807","url":"https:\/\/www.goodvibesmarina.com\/products\/cylinder-head-hose-starboard-for-johnson-evinrude-90-115-hp-outboards-replaces-omc-340975-sierra-18-70936","provider":"Good Vibes Marina","version":"1.0","type":"link"}