{"product_id":"sierra-18-3673-marine-thermostat-kit-140-degree-for-evinrude-johnson-3-cyl-90-degree-looper-outboards-replaces-omc-394409-434137","title":"Sierra 18-3673 Thermostat Kit for V-4 Crossflow Outboard Engines","description":"\u003cp\u003eThe Sierra 18-3673 Thermostat Kit is a complete replacement kit for the cooling system on V-4 Crossflow outboard engines. Rather than buying individual worn components separately, this kit bundles every part needed to service the thermostat housing in a single package, saving time on the workbench and ensuring the gaskets, grommet, relief valve, and springs are all matched and fresh at the same time.\u003c\/p\u003e\u003cp\u003eAt the core of the kit is the 18-3543 thermostat, paired with two thermostat gaskets (18-0675 and 18-0977) that seal the housing on both sides. An 18-2391 grommet seats the poppet valve assembly, while the 18-3564 poppet relief valve and 18-1243 valve springs regulate water flow and pressure relief during operation. The hardware components in the kit are iron construction for durability in a marine cooling environment.\u003c\/p\u003e\u003cp\u003eThis kit is built for V-4 Crossflow outboard engines. Sierra also offers the 18-3674 Thermostat Kit as the equivalent version for V-6 Crossflow engines, so buyers should confirm engine configuration before ordering to make sure the 18-3673 is the correct kit.\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 18-3673\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProduct Type:\u003c\/strong\u003e Thermostat Kit\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEngine Application:\u003c\/strong\u003e V-4 Crossflow\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eKit Contents:\u003c\/strong\u003e Thermostat, 2 thermostat gaskets, grommet, poppet relief valve, valve springs\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIncluded Thermostat Part Number:\u003c\/strong\u003e 18-3543\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial:\u003c\/strong\u003e Iron\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight:\u003c\/strong\u003e 0.22 pounds\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUPC:\u003c\/strong\u003e 808282258849\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInterchange Number:\u003c\/strong\u003e GLM 13270\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eFitment\u003c\/h3\u003e\u003cul\u003e\u003cli\u003eV-4 Crossflow outboard engines\u003c\/li\u003e\u003c\/ul\u003e\u003ch3\u003eReplaces (OEM)\u003c\/h3\u003e\u003cul\u003e\u003cli\u003eGLM 13270\u003c\/li\u003e\u003c\/ul\u003e\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\u003cp\u003e\u003cstrong\u003eWhat is included in the Sierra 18-3673 Thermostat Kit?\u003c\/strong\u003e The kit includes an 18-3543 thermostat, two thermostat gaskets (18-0675 and 18-0977), an 18-2391 grommet, an 18-3564 poppet relief valve, and 18-1243 valve springs.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhich engines does the 18-3673 thermostat kit fit?\u003c\/strong\u003e The Sierra 18-3673 Thermostat Kit is built for V-4 Crossflow outboard engines.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs the 18-3673 kit interchangeable with any OEM number?\u003c\/strong\u003e Yes, the Sierra 18-3673 Thermostat Kit is interchangeable with GLM 13270.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat material are the components in this thermostat kit made of?\u003c\/strong\u003e The hardware components in the Sierra 18-3673 Thermostat Kit are iron construction.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow much does the Sierra 18-3673 Thermostat Kit weigh?\u003c\/strong\u003e The Sierra 18-3673 Thermostat Kit weighs 0.22 pounds.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eDoes the 18-3673 kit include gaskets?\u003c\/strong\u003e Yes, two thermostat gaskets are included, part numbers 18-0675 and 18-0977, along with the rest of the 18-3673 kit components.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat thermostat comes with the Sierra 18-3673 kit?\u003c\/strong\u003e The Sierra 18-3673 Thermostat Kit uses the 18-3543 thermostat.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat is the difference between the 18-3673 and 18-3674 thermostat kits?\u003c\/strong\u003e The 18-3673 kit is for V-4 Crossflow engines, while the 18-3674 Thermostat Kit is the equivalent kit for V-6 Crossflow engines; both use the same 18-3543 thermostat but are separate part numbers for their respective engine applications.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eDoes the 18-3673 kit include a poppet relief valve and springs?\u003c\/strong\u003e Yes, the kit includes an 18-3564 poppet relief valve and 18-1243 valve springs along with the thermostat, gaskets, and grommet.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs the Sierra 18-3673 a complete thermostat housing rebuild kit?\u003c\/strong\u003e Yes, the Sierra 18-3673 Thermostat Kit bundles the thermostat, both gaskets, grommet, poppet relief valve, and valve springs needed to service the thermostat housing on a V-4 Crossflow outboard in one kit.\u003c\/p\u003e","brand":"Sierra","offers":[{"title":"Default Title","offer_id":48988157378779,"sku":"SIE-18-3673","price":42.75,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0839\/7586\/4539\/files\/SIE-18-3673_lg__10116.1558125136.500.750.jpg?v=1785187989","url":"https:\/\/www.goodvibesmarina.com\/products\/sierra-18-3673-marine-thermostat-kit-140-degree-for-evinrude-johnson-3-cyl-90-degree-looper-outboards-replaces-omc-394409-434137","provider":"Good Vibes Marina","version":"1.0","type":"link"}