{"product_id":"sierra-18-99428-trigger-for-mercury-mariner-4-cylinder-outboards","title":"Sierra Trigger for Mercury Mariner 4-Cylinder Outboard Motors - 18-99428","description":"\u003cp\u003eThe Sierra 18-99428 trigger is an ignition timing component built for Mercury and Mariner 4-cylinder outboard motors. The trigger works as part of the ignition system, sending timing signals to the switch box so spark fires at the correct point in the engine cycle. A trigger that has failed or is reading inconsistently is a common cause of hard starting, engine misfire, rough idle, or a no-spark condition on 4-cylinder Mercury and Mariner outboards. Replacing a worn or damaged trigger with a properly matched unit restores accurate ignition timing and helps the engine run smoothly across the RPM range.\u003c\/p\u003e\u003cp\u003eThis trigger is sold as a standalone replacement part, letting you address an ignition timing fault without replacing the entire ignition system. It is designed to install in place of the original trigger using the existing mounting points on 4-cylinder Mercury and Mariner powerheads.\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 18-99428\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProduct Name:\u003c\/strong\u003e Mercury Mariner Trigger - 4 Cyl.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCategory:\u003c\/strong\u003e Outboard Stator and Trigger\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEngine Configuration:\u003c\/strong\u003e 4-cylinder\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight:\u003c\/strong\u003e 0.5 pounds\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUPC:\u003c\/strong\u003e 808282394592\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eFitment\u003c\/h3\u003e\u003cul\u003e\u003cli\u003eMercury and Mariner 4-cylinder outboard motors\u003c\/li\u003e\u003c\/ul\u003e\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\u003cp\u003e\u003cstrong\u003eWhat is the Sierra 18-99428 trigger used for?\u003c\/strong\u003e The Sierra 18-99428 is an ignition trigger that sends timing signals to the switch box on Mercury and Mariner 4-cylinder outboard motors, allowing the ignition system to fire spark at the correct point in the engine cycle.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhich engines does the 18-99428 trigger fit?\u003c\/strong\u003e This trigger is designed for Mercury and Mariner 4-cylinder outboard motors.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat are signs that a trigger needs to be replaced?\u003c\/strong\u003e Hard starting, misfiring, rough idle, and no-spark conditions on a 4-cylinder Mercury or Mariner outboard can point to a failed or failing trigger such as the 18-99428.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow much does the 18-99428 trigger weigh?\u003c\/strong\u003e The Sierra 18-99428 trigger weighs 0.5 pounds.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs the 18-99428 an OEM or aftermarket part?\u003c\/strong\u003e The 18-99428 is a Sierra-branded replacement trigger manufactured to work as an ignition component on 4-cylinder Mercury and Mariner outboards.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eDoes the 18-99428 replace the entire ignition system?\u003c\/strong\u003e No, the 18-99428 is a standalone trigger component, letting you replace just the failed timing trigger rather than the full ignition system.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat is included when ordering part 18-99428?\u003c\/strong\u003e Ordering the Sierra 18-99428 includes the trigger unit itself for installation on a 4-cylinder Mercury or Mariner outboard.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eCan the 18-99428 trigger be used on non-Mercury outboards?\u003c\/strong\u003e The 18-99428 is built specifically for Mercury and Mariner 4-cylinder outboard motors.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat UPC is associated with the Sierra 18-99428 trigger?\u003c\/strong\u003e The Sierra 18-99428 trigger carries UPC 808282394592.\u003c\/p\u003e","brand":"Sierra","offers":[{"title":"Default Title","offer_id":48988443574491,"sku":"SIE-18-99428","price":127.13,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0839\/7586\/4539\/files\/i_6974e46b-4d59-4459-8075-60c29656def9.jpg?v=1785353674","url":"https:\/\/www.goodvibesmarina.com\/products\/sierra-18-99428-trigger-for-mercury-mariner-4-cylinder-outboards","provider":"Good Vibes Marina","version":"1.0","type":"link"}