{"product_id":"mercury-spark-plug-ac-41-993-884019001","title":"Mercury MerCruiser Spark Plug AC 41-993 884019001 (Superseded to 8M0204739)","description":"\u003ch2\u003eMercury MerCruiser Spark Plug — AC 41-993 \/ 884019001\u003c\/h2\u003e\n\n\u003ctable\u003e\n\u003ctr\u003e\n\u003cth\u003eField\u003c\/th\u003e\n\u003cth\u003eDetail\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003ePart Number\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e884019001 \/ 33-884019001\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eOriginal Plug\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eACDelco AC 41-993\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eBrand\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eMercury Marine \/ MerCruiser\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eOfficial Product Type\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eSpark Plug — Platinum (OEM original service plug)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eSupersedes\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e41-932 \/ Mercury 884019\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eReplaced By (Current)\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003ca href=\"\/products\/mercury-mercruiser-ngk-spark-plug-itr4a15-8m0204739-4-pack\"\u003eQuicksilver 8M0204739 — NGK ITR4A-15 Laser Iridium\u003c\/a\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eSystem\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eIgnition\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eSold As\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eIndividually (one plug per order unless specified)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\n\n\u003ch3\u003eEngine Family \u0026amp; Compatible Applications\u003c\/h3\u003e\n\u003cp\u003eOriginally specified for GM-based MerCruiser gasoline engines. Always confirm by engine serial number before ordering — similar engines can require different plug specs or gap settings.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e4.3L MPI V6\u003c\/li\u003e\n\u003cli\u003e5.0L MPI V8\u003c\/li\u003e\n\u003cli\u003e5.7L \/ 350 MAG MPI V8\u003c\/li\u003e\n\u003cli\u003e6.2L MPI V8\u003c\/li\u003e\n\u003cli\u003e4.3L, 5.0L and 5.7L carbureted variants\u003c\/li\u003e\n\u003cli\u003eScorpion 350\u003c\/li\u003e\n\u003cli\u003eScorpion 377 HO\u003c\/li\u003e\n\u003cli\u003e383 MAG Stroker (selected applications)\u003c\/li\u003e\n\u003cli\u003eAdditional GM-based MerCruiser gasoline engines where the original parts catalog specifies 884019001\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eSerial Number \u0026amp; Gap Requirements\u003c\/h3\u003e\n\u003cp\u003eConfirm the engine model and MerCruiser serial number before ordering. The AC 41-993 was used with more than one gap specification depending on engine type:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e~1.14 mm \/ 0.045 in.\u003c\/strong\u003e — selected carbureted applications\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e~1.52 mm \/ 0.060 in.\u003c\/strong\u003e — most MPI applications\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eAlways follow the gap specification in the applicable Mercury service manual or engine owner's manual for your serial range. Do not assume one gap applies to all engines using this part number.\u003c\/p\u003e\n\n\u003ch3\u003eWhen to Replace Spark Plugs\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eWorn, eroded, or fouled electrodes\u003c\/li\u003e\n\u003cli\u003eHeavy carbon, fuel, or oil deposits\u003c\/li\u003e\n\u003cli\u003eCorrosion on the shell or terminal\u003c\/li\u003e\n\u003cli\u003eCracked or damaged ceramic insulator\u003c\/li\u003e\n\u003cli\u003eDifficult starting, rough idle, or intermittent misfire\u003c\/li\u003e\n\u003cli\u003eReduced acceleration or engine performance\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eFor multi-cylinder engines, replacing the complete set together helps maintain consistent ignition performance.\u003c\/p\u003e\n\n\u003ch3\u003eService Interval\u003c\/h3\u003e\n\u003cp\u003eMercury typically specifies spark plug inspection at each annual service and replacement every 200–300 hours of operation, or per the interval stated in your engine's owner's manual. Actual interval varies by engine type and use pattern.\u003c\/p\u003e\n\n\u003ch3\u003eInstallation Notes\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eVerify the plug specification and gap against the engine serial number and Mercury service information before installing\u003c\/li\u003e\n\u003cli\u003eInstall into a cool cylinder head; follow Mercury's torque specification\u003c\/li\u003e\n\u003cli\u003eWhile servicing plugs, inspect spark-plug wires, boots, distributor (where equipped), and ignition coils for deterioration or corrosion\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eAlternate \u0026amp; Superseded Part Numbers\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e884019001\u003c\/strong\u003e — original Mercury \/ MerCruiser number\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e33-884019001\u003c\/strong\u003e — Mercury catalog format\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAC 41-993\u003c\/strong\u003e — original ACDelco designation\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e41-932\u003c\/strong\u003e — earlier ACDelco plug superseded by AC 41-993\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e884019\u003c\/strong\u003e — earlier Mercury reference (AC 41-932 applications)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e8M0204739\u003c\/strong\u003e — current Mercury \/ Quicksilver replacement\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eNGK ITR4A-15\u003c\/strong\u003e — current replacement plug designation\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eTechnical FAQ\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eQ: The replacement plug looks different from the one I removed — is that normal?\u003c\/strong\u003e\u003cbr\u003e\nA: Yes. Mercury has moved this application to the \u003ca href=\"\/products\/mercury-mercruiser-ngk-spark-plug-itr4a15-8m0204739-4-pack\"\u003eQuicksilver 8M0204739 NGK ITR4A-15 Laser Iridium\u003c\/a\u003e, which has a different appearance from the original AC 41-993 platinum plug. Focus on serial-number fitment, not visual match.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eQ: Can I use the same gap as the plug I removed?\u003c\/strong\u003e\u003cbr\u003e\nA: Not necessarily. Gap specification varies by engine model and serial range. Always verify against your Mercury service manual.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eQ: Do I need to buy a full set?\u003c\/strong\u003e\u003cbr\u003e\nA: This listing is sold individually. Order the quantity matching your engine's cylinder count. View the \u003ca href=\"\/products\/mercury-mercruiser-ngk-spark-plug-itr4a15-8m0204739-4-pack\"\u003e8M0204739 4-pack\u003c\/a\u003e if you need the current replacement in a multi-pack.\u003c\/p\u003e\n\n\u003ch3\u003eRelated Parts\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\u003ca href=\"\/products\/mercury-mercruiser-ngk-spark-plug-itr4a15-8m0204739-4-pack\"\u003eQuicksilver 8M0204739 NGK ITR4A-15 — Current Replacement (4-pack)\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003chr\u003e\n\u003ch3\u003eParts Desk Insights\u003c\/h3\u003e\n\u003cp\u003eIf your engine originally calls for 884019001 \/ AC 41-993, the most common customer question is whether the newer-looking \u003ca href=\"\/products\/mercury-mercruiser-ngk-spark-plug-itr4a15-8m0204739-4-pack\"\u003e8M0204739 NGK Iridium\u003c\/a\u003e is the right fit — it is, for most applications in this family, but always verify by serial number. Customers frequently order one plug when they need a full set; confirm cylinder count at the time of order. The gap setting is the other common issue — different applications within the same engine family use different gaps, so verify before installation rather than reusing the old plug's gap.\u003c\/p\u003e","brand":"MERC","offers":[{"title":"Default Title","offer_id":43563901550628,"sku":"884019001","price":19.42,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0743\/5799\/7604\/files\/2160b686-8ea4-46f6-a6bd-485e0b114e42.png?v=1775776616","url":"https:\/\/marisolmarine.com\/products\/mercury-spark-plug-ac-41-993-884019001","provider":"Marisol Marine Company","version":"1.0","type":"link"}