{"product_id":"sierra-fuel-water-separator-filter-18-7945-4-pack-oem-fit-replacement-for-marine-and-small-engine-systems","title":"Sierra fuel\/water separator filter 18-7945 — 4-pack OEM-fit replacement for marine and small-engine systems","description":"\u003cp\u003e\u003cstrong\u003eThe Sierra 18-7945 is a fuel\/water separator replacement filter sold as a 4-pack, designed to trap water and contaminants from marine and small-engine fuel systems to protect injectors and carburetors.\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003cp\u003eThis four-pack of Sierra SIE 7945 fuel water separator filters offers a straightforward maintenance solution for boaters and technicians who need consistent fuel filtration and spare parts on hand. Each cartridge is sized and shaped to match OEM specifications, making it a plug-and-play replacement for compatible in-line and spin-on fuel systems. Keeping fresh filters on board reduces downtime and helps engines run more reliably by removing particulates and free water before fuel reaches sensitive components.\u003c\/p\u003e\n\n\u003ch3\u003eHow does the Sierra 18-7945 improve fuel system reliability?\u003c\/h3\u003e\n\u003cp\u003eThe filter captures solid particles and separates free water from fuel prior to combustion, helping reduce wear and fouling of fuel pumps, injectors, and carburetors. Using a dedicated separator element means less chance of water-related corrosion and fewer performance interruptions while underway.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eRemoves particulate contaminants to protect metering components\u003c\/li\u003e\n  \u003cli\u003eSeparates and sheds free water to prevent injector damage\u003c\/li\u003e\n  \u003cli\u003eConsistent dimensions for correct seating and sealing\u003c\/li\u003e\n  \u003cli\u003eIncludes four spare cartridges for scheduled maintenance\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhich engines and systems can use the SIE 7945 filter?\u003c\/h3\u003e\n\u003cp\u003eThe Sierra 18-7945 is intended as a replacement element for compatible marine and small-engine fuel\/water separator housings that accept the SIE 7945 specification. Confirm compatibility with your engine or filter housing by checking part numbers and physical fit before purchase.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eDesigned for many marine diesel and gasoline pre-filter housings\u003c\/li\u003e\n  \u003cli\u003eSuitable for in-line and spin-on separator assemblies matching 18-7945\u003c\/li\u003e\n  \u003cli\u003eCommonly used in recreational boats and small commercial craft\u003c\/li\u003e\n  \u003cli\u003eWorks as a direct replacement when OEM part numbers align\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eHow often should these filters be changed, and what signals to replace them?\u003c\/h3\u003e\n\u003cp\u003eReplacement intervals vary by operating hours, fuel quality, and environmental conditions; a typical schedule is during routine engine service or at manufacturer-recommended mileage\/hours. Replace the cartridge sooner if you notice fuel starvation, loss of power, or visible water in the filter bowl.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eFollow engine or filter housing manufacturer’s recommended schedule\u003c\/li\u003e\n  \u003cli\u003eInspect the bowl regularly; replace if water or heavy sludge appears\u003c\/li\u003e\n  \u003cli\u003eChange before long-season storage or after running on suspect fuel\u003c\/li\u003e\n  \u003cli\u003eKeep the included four-pack on board for quick swaps and spares\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhat are the practical benefits of buying the 4-pack version?\u003c\/h3\u003e\n\u003cp\u003ePurchasing four replacement elements at once simplifies upkeep and ensures you have spares ready for scheduled maintenance or unexpected contamination events. Bulk packaging often reduces per-filter cost and lowers the chance of running without a proper replacement when you need one.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eMultiple replacements available without immediate reordering\u003c\/li\u003e\n  \u003cli\u003eCost-effective for seasonal or fleet maintenance planning\u003c\/li\u003e\n  \u003cli\u003eReduces downtime by keeping spare parts onboard or in the shop\u003c\/li\u003e\n  \u003cli\u003eUniform filtration performance across service intervals\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eWho is this for: boat owners, marine mechanics, and fleet operators who run diesel or gasoline engines with compatible fuel\/water separator housings and want a reliable, OEM-style replacement filter available in convenient multiple quantities. Choose the Sierra 18-7945 4-pack if you prioritize consistent fuel protection, easy installation, and having spare elements ready for scheduled servicing or emergency swaps.\u003c\/p\u003e\n\u003csection class=\"product-faq-snippet\"\u003e\u003ch3\u003eFAQ\u003c\/h3\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cp class=\"faq-q\"\u003eQ: Is the Sierra 18-7945 a direct OEM replacement?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: It fits housings designed for the SIE 7945 specification; verify your OEM part number and physical dimensions for a direct replacement.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cp class=\"faq-q\"\u003eQ: Can I use the filter for both diesel and gasoline engines?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: Yes, when the housing and engine manufacturer approve the SIE 7945 design for that fuel type; always confirm compatibility before use.\u003c\/p\u003e\n\u003c\/div\u003e\u003c\/section\u003e","brand":"Sierra","offers":[{"title":"Default Title","offer_id":55168479789399,"sku":"B00WF9O4PQ","price":76.89,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1050\/1524\/7191\/files\/sierra-18-7945-front-view.jpg?v=1790405095","url":"https:\/\/britishgarage.co.uk\/products\/sierra-fuel-water-separator-filter-18-7945-4-pack-oem-fit-replacement-for-marine-and-small-engine-systems","provider":"British Garage","version":"1.0","type":"link"}