{"product_id":"sierra-18-3109-water-tube-guide-for-mercury-mercruiser-outboard-cooling-systems-replaces-23-29804-23-52928","title":"Sierra 18-3109 Water Tube Guide for Mercury Outboard Cooling Systems, White Plastic","description":"\u003cp\u003eThe Sierra 18-3109 Water Tube Guide is a replacement component for the Mercury outboard cooling system, engineered to direct water flow through the tube passage that feeds the engine's cooling circuit. It is molded from durable white plastic, giving it corrosion resistance in the wet, salt-exposed environment around an outboard's lower cooling components, unlike a metal guide that would be prone to rust or galvanic corrosion over time.\u003c\/p\u003e\u003cp\u003eThis water tube guide is a small but important part of the cooling system: if it wears, cracks, or goes missing, the water tube can lose proper alignment and reduce the amount of raw water reaching the engine, which can lead to overheating. Replacing a worn or damaged guide with the correct Sierra 18-3109 part restores proper tube seating and cooling flow. Sierra manufactures this part to meet or exceed the specifications of the original equipment it replaces, so it installs and functions as a direct equivalent.\u003c\/p\u003e\u003cp\u003eThe 18-3109 is cross-referenced to the GLM 12820 water tube guide as well as Mallory 9-45623 and several Mercruiser\/Mercury part numbers, making it a straightforward swap for owners replacing a worn factory guide on compatible Mercury outboard cooling systems.\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 18-3109\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProduct Name:\u003c\/strong\u003e Water Tube Guide\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCategory:\u003c\/strong\u003e Mercury Outboard Cooling System\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial:\u003c\/strong\u003e Plastic\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 0.02 pounds\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePackage Dimensions:\u003c\/strong\u003e 3.048 centimeters H x 8.89 centimeters L x 5.08 centimeters W\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUPC:\u003c\/strong\u003e 030999315465\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCountry of Origin:\u003c\/strong\u003e United States\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eFitment\u003c\/h3\u003e\u003cp\u003eFits the Mercury outboard cooling system as a replacement water tube guide.\u003c\/p\u003e\u003ch3\u003eReplaces (OEM)\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003eGLM 12820\u003c\/li\u003e\n\u003cli\u003eMallory 9-45623\u003c\/li\u003e\n\u003cli\u003eMercruiser\/Mercury 23-52928\u003c\/li\u003e\n\u003cli\u003eMercruiser\/Mercury 23-29804\u003c\/li\u003e\n\u003cli\u003eMercruiser\/Mercury 23-29804T\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\u003cp\u003e\u003cstrong\u003eWhat is the Sierra 18-3109 used for?\u003c\/strong\u003e It is a water tube guide for the Mercury outboard cooling system, positioning the water tube so raw water flows correctly into the engine's cooling circuit.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs the Sierra 18-3109 a genuine Sierra part or aftermarket?\u003c\/strong\u003e The 18-3109 is manufactured by Sierra as a direct replacement part, built to meet or exceed the specifications of the original equipment component it replaces.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat OEM and cross-reference numbers does the 18-3109 replace?\u003c\/strong\u003e The Sierra 18-3109 cross-references to GLM 12820, Mallory 9-45623, and Mercruiser\/Mercury numbers 23-52928, 23-29804, and 23-29804T.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat material is the water tube guide made of?\u003c\/strong\u003e The Sierra 18-3109 Water Tube Guide is made of white plastic, which resists corrosion in the wet environment around an outboard's cooling components.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow much does the 18-3109 weigh?\u003c\/strong\u003e The Sierra 18-3109 Water Tube Guide weighs 0.02 pounds.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat color is the Sierra 18-3109 water tube guide?\u003c\/strong\u003e This water tube guide is white.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat are the package dimensions of the 18-3109?\u003c\/strong\u003e The Sierra 18-3109 ships in a package measuring 3.048 centimeters high by 8.89 centimeters long by 5.08 centimeters wide.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWill the GLM 12820 fit in place of the Sierra 18-3109?\u003c\/strong\u003e Yes, the GLM 12820 is cross-referenced to the Sierra 18-3109 as an equivalent water tube guide.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat does a worn water tube guide cause if not replaced?\u003c\/strong\u003e A worn or cracked water tube guide, like the one the Sierra 18-3109 replaces, can allow the water tube to misalign and reduce raw water flow to the engine, contributing to overheating.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat is included when you order the 18-3109?\u003c\/strong\u003e The order includes one Sierra 18-3109 Water Tube Guide.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs the Sierra 18-3109 only for Mercury outboards?\u003c\/strong\u003e The 18-3109 is categorized for the Mercury outboard cooling system and is cross-referenced to Mercruiser\/Mercury OEM numbers.\u003c\/p\u003e","brand":"Sierra","offers":[{"title":"Default Title","offer_id":48988140372187,"sku":"SIE-18-3109","price":5.05,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0839\/7586\/4539\/files\/SIE-18-3109_lg__37878.1709039940.500.750.jpg?v=1785189005","url":"https:\/\/www.goodvibesmarina.com\/products\/sierra-18-3109-water-tube-guide-for-mercury-mercruiser-outboard-cooling-systems-replaces-23-29804-23-52928","provider":"Good Vibes Marina","version":"1.0","type":"link"}