{"product_id":"sierra-18-97350-carburetor-kit-mercury-9-9-25-hp","title":"Sierra 18-97350 Carburetor Kit | Mercury 9.9-25 HP","description":"\u003cp class=\"nvn-hero\"\u003eThe Sierra 18-97350 is a complete carburetor rebuild kit for Mercury 9.9, 15, 20, and 25 HP outboards. It packs the gaskets, o-rings, seals, diaphragms, and hardware you need to bring a gummed-up carb back to clean idling and crisp throttle response. Built to meet or exceed the original parts it replaces.\u003c\/p\u003e\n\n\u003cdiv class=\"nvn-description\"\u003e\n\u003cp\u003eWhen a Mercury 9.9, 15, 20, or 25 horsepower outboard starts hunting at idle, floods on a hot restart, or dies the moment you back off the throttle, the carburetor is usually the culprit. Today's ethanol-blended fuel is hard on the soft parts inside a carb, and they don't last forever. This Sierra 18-97350 carburetor kit gives you everything you need to bring that carb back to life: gaskets, o-rings, seals, diaphragms, and the small hardware that always seems to walk off the bench.\u003c\/p\u003e\n\u003cp\u003eSierra builds its replacement parts to meet or exceed the original equipment they replace. They supply parts to a lot of the same engine builders and boat manufacturers every day, so you're not gambling on a no-name bargain kit here. The diaphragms are cut to the correct thickness, the o-rings are sized to seat the way they should, and the gaskets seal on the first pull-down. That matters when you've got the cowling off and don't want to do the job twice.\u003c\/p\u003e\n\u003cp\u003eMost of these carbs fail the same way. The boat sits through the off-season with fuel in the bowl, the ethanol pulls moisture and leaves varnish behind, and the tiny metering passages gum up. Then spring comes and the engine won't idle, or it runs lean and hot at cruise. A full kit like this replaces every wear item at once instead of chasing one bad o-ring at a time. Cleaning the carb without new soft parts is a temporary fix at best, because the old diaphragms and o-rings have already taken a set and won't seal like they did new. Do it right and the motor idles clean and picks up crisp again.\u003c\/p\u003e\n\u003cp\u003eA few things we've learned rigging these. First, confirm your exact carburetor model before you start, since a couple of the 25 HP variants use a slightly different diaphragm. Second, wet the new diaphragm before you set it and take your time on the alignment, because a dry diaphragm tears easily. Third, if the fuel pump runs off the same carburetor, replace that pump diaphragm at the same time or the lean condition comes right back. And while you're in there, put on a fresh inline fuel filter and run ethanol-rated fuel line so you're not back at the bench next season.\u003c\/p\u003e\n\u003cp\u003eOne heads-up on the hardware. The kit includes the screws and small pieces most of these rebuilds call for, but a few tiller-handle setups use slightly different length fasteners. So keep your old hardware until you've confirmed the new pieces thread in clean. It's a five-minute check that saves a headache.\u003c\/p\u003e\n\u003cp\u003eYou don't need a shop full of specialty tools for this job. A clean bench, a set of screwdrivers, some carb cleaner, and an hour or two of patience will get most boaters through it. Lay the parts out in order as they come off, snap a couple of phone photos before you disassemble, and the reassembly goes smooth. It's a very doable job for anyone comfortable turning their own wrenches.\u003c\/p\u003e\n\u003cp\u003eThese smaller Mercs show up on everything from tiller-steer jon boats to sailboat kicker motors, and access behind the cowling can get tight on the 15 and 20 HP models. Give yourself room to work. One honest caution: if the engine has cracked pulse lines or a warped carb body, a rebuild kit won't fix that. Sort out the hard parts first, then this kit handles the soft parts.\u003c\/p\u003e\n\u003cp\u003eFor a Mercury 9.9 to 25 HP outboard that's earned a tune-up, this is the kit that gets it running like it should. A carburetor rebuild is one of the highest-value jobs you can do on a small outboard, since it restores fuel economy, easy starting, and reliable idle for a fraction of the cost of a shop visit or a new carb. Order before 3 PM ET and we'll ship it same day on in-stock units.\u003c\/p\u003e\n\u003c\/div\u003e\n\n\u003ch2\u003eKey Features\u003c\/h2\u003e\n\u003cul class=\"nvn-features\"\u003e\n  \u003cli\u003eComplete carburetor rebuild kit for Mercury 9.9, 15, 20, and 25 HP outboards\u003c\/li\u003e\n  \u003cli\u003eIncludes gaskets, o-rings, seals, diaphragms, and hardware in one package\u003c\/li\u003e\n  \u003cli\u003eBuilt to meet or exceed the original equipment part it replaces\u003c\/li\u003e\n  \u003cli\u003eCorrectly sized diaphragms restore proper fuel metering and idle quality\u003c\/li\u003e\n  \u003cli\u003eFresh o-rings and seals stop the small leaks that cause lean running\u003c\/li\u003e\n  \u003cli\u003eReplaces every soft wear item at once so you rebuild the carb properly the first time\u003c\/li\u003e\n  \u003cli\u003eSierra supplies OEM engine builders and boat manufacturers, so fit and quality are proven\u003c\/li\u003e\n  \u003cli\u003eA cost-effective fix for hard starting, rough idle, and stalling on ethanol fuel\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cdiv class=\"nvn-trust\"\u003e\n  \u003ch2\u003eWhy Buy from NVN Marine\u003c\/h2\u003e\n  \u003cul\u003e\n    \u003cli\u003eAuthorized Sierra Marine reseller, full manufacturer warranty\u003c\/li\u003e\n    \u003cli\u003eNMEA member and ABYC certified, advice from real boat techs\u003c\/li\u003e\n    \u003cli\u003eSame-day shipping before 3 PM ET on in-stock items\u003c\/li\u003e\n    \u003cli\u003eNY headquarters and Fort Lauderdale flagship retail store\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/div\u003e\n\n\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\n\u003cdiv class=\"nvn-faq\"\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eWhich engines does this carburetor kit fit?\u003c\/summary\u003e\n    \u003cp\u003eIt's designed for Mercury Marine 9.9, 15, 20, and 25 horsepower outboards. Because there are running changes across those years, confirm your exact carburetor model before ordering, since a couple of the 25 HP variants use a slightly different diaphragm.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eWhat's included in the Sierra 18-97350 kit?\u003c\/summary\u003e\n    \u003cp\u003eGaskets, o-rings, seals, diaphragms, and the small hardware needed for the rebuild. It's a complete soft-parts kit, so you replace every wear item in one job instead of chasing one bad part at a time.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eHow do I know my carburetor needs a rebuild?\u003c\/summary\u003e\n    \u003cp\u003eClassic signs are a rough or hunting idle, hard starting when the engine is hot, stalling when you drop off the throttle, and running lean or hot at cruise. These usually point to old diaphragms, dried o-rings, and varnish in the passages from ethanol fuel.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eShould I replace the fuel pump diaphragm at the same time?\u003c\/summary\u003e\n    \u003cp\u003eYes, if the fuel pump runs off the same carburetor. Skipping it is the number one reason a lean condition comes right back after a rebuild. Do the whole job while you have it apart.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eIs this an OEM-quality kit?\u003c\/summary\u003e\n    \u003cp\u003eSierra builds its parts to meet or exceed the original equipment they replace, and they supply many of the same OEM engine builders and boat manufacturers. It's not a bargain no-name kit.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eDo I need special tools to install it?\u003c\/summary\u003e\n    \u003cp\u003eNo. A set of screwdrivers, some carburetor cleaner, a clean bench, and a couple of hours of patience will get most boaters through it. Lay the parts out in order and photograph the carb before you take it apart.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eAny tips to keep the carb from gumming up again?\u003c\/summary\u003e\n    \u003cp\u003eRun ethanol-rated fuel line and add a fresh inline fuel filter during the rebuild. Try not to leave ethanol fuel sitting in the carb for more than about a month, since that's when the o-rings swell and the passages varnish over.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eWill this kit fix any running problem on my outboard?\u003c\/summary\u003e\n    \u003cp\u003eIt fixes carburetor soft-part issues, which cover most idle and fuel-delivery complaints. It won't fix cracked pulse lines, a warped carb body, or ignition problems. Sort out any hard-part damage first, then this kit handles the seals and diaphragms.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eWhat is the part number and how do I verify fitment?\u003c\/summary\u003e\n    \u003cp\u003eThis is Sierra part 18-97350, UPC 808282387006. Match it against your engine's model and serial number and your carburetor's casting number to be sure you've got the right variant before you start the job.\u003c\/p\u003e\n  \u003c\/details\u003e\n\u003c\/div\u003e\n\n\u003ch2\u003eTechnical Specifications\u003c\/h2\u003e\n\u003ctable class=\"nvn-specs\"\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003cth\u003eTitle\u003c\/th\u003e\n\u003ctd\u003eSierra 18-97350 Carburetor Kit for Mercury 9.9 to 25 HP Outboards\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eBrand\u003c\/th\u003e\n\u003ctd\u003eSierra Marine\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eManufacturer Part Number\u003c\/th\u003e\n\u003ctd\u003e18-97350\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eUPC\u003c\/th\u003e\n\u003ctd\u003e808282387006\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eKit Type\u003c\/th\u003e\n\u003ctd\u003eCarburetor Kit\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eEngine Compatibility\u003c\/th\u003e\n\u003ctd\u003eMercury Marine 9.9 to 25 HP Outboard Engines\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eHorsepower Range\u003c\/th\u003e\n\u003ctd\u003e9.9 to 25 HP\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eIncluded Components\u003c\/th\u003e\n\u003ctd\u003eGaskets, O-Rings, Seals, Diaphragms, Hardware\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eEngine Type\u003c\/th\u003e\n\u003ctd\u003eOutboard\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eApplication\u003c\/th\u003e\n\u003ctd\u003eCarburetor rebuild\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eQuality Standard\u003c\/th\u003e\n\u003ctd\u003eMeets or exceeds OEM part it replaces\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth\u003eSold As\u003c\/th\u003e\n\u003ctd\u003eComplete kit\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003cscript type=\"application\/ld+json\"\u003e\n{\n    \"@context\": \"https:\/\/schema.org\",\n    \"@type\": \"FAQPage\",\n    \"mainEntity\": [\n        {\n            \"@type\": \"Question\",\n            \"name\": \"Which engines does this carburetor kit fit?\",\n            \"acceptedAnswer\": {\n                \"@type\": \"Answer\",\n                \"text\": \"It's designed for Mercury Marine 9.9, 15, 20, and 25 horsepower outboards. Because there are running changes across those years, confirm your exact carburetor model before ordering, since a couple of the 25 HP variants use a slightly different diaphragm.\"\n            }\n        },\n        {\n            \"@type\": \"Question\",\n            \"name\": \"What's included in the Sierra 18-97350 kit?\",\n            \"acceptedAnswer\": {\n                \"@type\": \"Answer\",\n                \"text\": \"Gaskets, o-rings, seals, diaphragms, and the small hardware needed for the rebuild. It's a complete soft-parts kit, so you replace every wear item in one job instead of chasing one bad part at a time.\"\n            }\n        },\n        {\n            \"@type\": \"Question\",\n            \"name\": \"How do I know my carburetor needs a rebuild?\",\n            \"acceptedAnswer\": {\n                \"@type\": \"Answer\",\n                \"text\": \"Classic signs are a rough or hunting idle, hard starting when the engine is hot, stalling when you drop off the throttle, and running lean or hot at cruise. These usually point to old diaphragms, dried o-rings, and varnish in the passages from ethanol fuel.\"\n            }\n        },\n        {\n            \"@type\": \"Question\",\n            \"name\": \"Should I replace the fuel pump diaphragm at the same time?\",\n            \"acceptedAnswer\": {\n                \"@type\": \"Answer\",\n                \"text\": \"Yes, if the fuel pump runs off the same carburetor. Skipping it is the number one reason a lean condition comes right back after a rebuild. Do the whole job while you have it apart.\"\n            }\n        },\n        {\n            \"@type\": \"Question\",\n            \"name\": \"Is this an OEM-quality kit?\",\n            \"acceptedAnswer\": {\n                \"@type\": \"Answer\",\n                \"text\": \"Sierra builds its parts to meet or exceed the original equipment they replace, and they supply many of the same OEM engine builders and boat manufacturers. It's not a bargain no-name kit.\"\n            }\n        },\n        {\n            \"@type\": \"Question\",\n            \"name\": \"Do I need special tools to install it?\",\n            \"acceptedAnswer\": {\n                \"@type\": \"Answer\",\n                \"text\": \"No. A set of screwdrivers, some carburetor cleaner, a clean bench, and a couple of hours of patience will get most boaters through it. Lay the parts out in order and photograph the carb before you take it apart.\"\n            }\n        },\n        {\n            \"@type\": \"Question\",\n            \"name\": \"Any tips to keep the carb from gumming up again?\",\n            \"acceptedAnswer\": {\n                \"@type\": \"Answer\",\n                \"text\": \"Run ethanol-rated fuel line and add a fresh inline fuel filter during the rebuild. Try not to leave ethanol fuel sitting in the carb for more than about a month, since that's when the o-rings swell and the passages varnish over.\"\n            }\n        },\n        {\n            \"@type\": \"Question\",\n            \"name\": \"Will this kit fix any running problem on my outboard?\",\n            \"acceptedAnswer\": {\n                \"@type\": \"Answer\",\n                \"text\": \"It fixes carburetor soft-part issues, which cover most idle and fuel-delivery complaints. It won't fix cracked pulse lines, a warped carb body, or ignition problems. Sort out any hard-part damage first, then this kit handles the seals and diaphragms.\"\n            }\n        },\n        {\n            \"@type\": \"Question\",\n            \"name\": \"What is the part number and how do I verify fitment?\",\n            \"acceptedAnswer\": {\n                \"@type\": \"Answer\",\n                \"text\": \"This is Sierra part 18-97350, UPC 808282387006. Match it against your engine's model and serial number and your carburetor's casting number to be sure you've got the right variant before you start the job.\"\n            }\n        }\n    ]\n}\n\u003c\/script\u003e\n","brand":"Sierra Marine","offers":[{"title":"Default Title","offer_id":45061589205085,"sku":"2008572","price":96.09,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0299\/7266\/0317\/files\/ImageServerAPI_e1cbebf9-47ef-4368-9eb8-91b50f31a1c0.png?v=1789552577","url":"https:\/\/nvnmarine.com\/products\/sierra-18-97350-carburetor-kit-mercury-9-9-25-hp","provider":"NVN Marine","version":"1.0","type":"link"}