{"product_id":"4731a6-4731a8-mercury-trigger-genuine-used-part","title":"4731A6 4731A8 Mercury Trigger | Genuine Used Part","description":"\u003cp\u003e\n 🔧 Product Description\n\u003c\/p\u003e\n\u003cp\u003e\n \u003cbr\u003e\n\u003c\/p\u003e\n\u003cp\u003e\n Genuine Used Mercury Mariner 40HP Twin-Cylinder Trigger Plate - Part Numbers: 4731A6 and 4731A8\n\u003c\/p\u003e\n\u003cp\u003e\n \u003cbr\u003e\n\u003c\/p\u003e\n\u003cp\u003e\n A genuine pre-owned Mercury and Mariner trigger-plate assembly for selected 40HP and 402 twin-cylinder two-stroke outboards.\n\u003c\/p\u003e\n\u003cp\u003e\n \u003cbr\u003e\n\u003c\/p\u003e\n\u003cp\u003e\n Part number 4731A6 supersedes to 4731A8. The trigger assembly is mounted beneath the flywheel and produces the ignition-timing signals required by the switchbox.\n\u003c\/p\u003e\n\u003cp\u003e\n \u003cbr\u003e\n\u003c\/p\u003e\n\u003cp\u003e\n The complete trigger plate also rotates with the throttle and spark-advance linkage to alter ignition timing as engine speed increases.\n\u003c\/p\u003e\n\u003cp\u003e\n \u003cbr\u003e\n\u003c\/p\u003e\n\u003cp\u003e\n ⚙️ Key Features\n\u003c\/p\u003e\n\u003cp\u003e\n \u003cbr\u003e\n\u003c\/p\u003e\n\u003cp\u003e\n • Genuine Mercury or Mariner used trigger plate\n\u003c\/p\u003e\n\u003cp\u003e\n • Earlier OEM number 4731A6\n\u003c\/p\u003e\n\u003cp\u003e\n • Later service number 4731A8\n\u003c\/p\u003e\n\u003cp\u003e\n • Designed for selected 40HP and 402 twin-cylinder engines\n\u003c\/p\u003e\n\u003cp\u003e\n • Mechanical spark-advance configuration\n\u003c\/p\u003e\n\u003cp\u003e\n • Original Mercury ignition component\n\u003c\/p\u003e\n\u003cp\u003e\n \u003cbr\u003e\n\u003c\/p\u003e\n\u003cp\u003e\n 🔄 Supersession \u0026amp; Cross Reference\n\u003c\/p\u003e\n\u003cp\u003e\n \u003cbr\u003e\n\u003c\/p\u003e\n\u003cp\u003e\n OEM Supersession Chain:\n\u003c\/p\u003e\n\u003cp\u003e\n \u003cbr\u003e\n\u003c\/p\u003e\n\u003cp\u003e\n • Mercury 4731A6 - Earlier trigger-plate assembly\n\u003c\/p\u003e\n\u003cp\u003e\n • Mercury 4731A8 - Later functional replacement\n\u003c\/p\u003e\n\u003cp\u003e\n • The later assembly may differ visually while remaining the verified service replacement\n\u003c\/p\u003e\n\u003cp\u003e\n \u003cbr\u003e\n\u003c\/p\u003e\n\u003cp\u003e\n OEM \/ Related Numbers:\n\u003c\/p\u003e\n\u003cp\u003e\n \u003cbr\u003e\n\u003c\/p\u003e\n\u003cp\u003e\n • 4731A6\n\u003c\/p\u003e\n\u003cp\u003e\n • 4731A8\n\u003c\/p\u003e\n\u003cp\u003e\n • 338-4731A6\n\u003c\/p\u003e\n\u003cp\u003e\n • 338-4731A8\n\u003c\/p\u003e\n\u003cp\u003e\n • OEM Description: Trigger Plate Assembly\n\u003c\/p\u003e\n\u003cp\u003e\n • OEM Description: Trigger Assembly\n\u003c\/p\u003e\n\u003cp\u003e\n • Engine Family: Mercury 402 \/ 40HP Two-Cylinder\n\u003c\/p\u003e\n\u003cp\u003e\n \u003cbr\u003e\n\u003c\/p\u003e\n\u003cp\u003e\n Aftermarket \/ Verified Equivalents:\n\u003c\/p\u003e\n\u003cp\u003e\n \u003cbr\u003e\n\u003c\/p\u003e\n\u003cp\u003e\n • No verified new aftermarket equivalent\n\u003c\/p\u003e\n\u003cp\u003e\n • Genuine used, new-old-stock or professionally rebuilt assemblies are generally required\n\u003c\/p\u003e\n\u003cp\u003e\n \u003cbr\u003e\n\u003c\/p\u003e\n\u003cp\u003e\n 🚤 Compatibility\n\u003c\/p\u003e\n\u003cp\u003e\n \u003cbr\u003e\n\u003c\/p\u003e\n\u003cp\u003e\n Commonly used on:\n\u003c\/p\u003e\n\u003cp\u003e\n \u003cbr\u003e\n\u003c\/p\u003e\n\u003cp\u003e\n • Mercury 402 outboards\n\u003c\/p\u003e\n\u003cp\u003e\n • Mercury 40HP twin-cylinder outboards\n\u003c\/p\u003e\n\u003cp\u003e\n • Mariner equivalents using the Mercury ignition system\n\u003c\/p\u003e\n\u003cp\u003e\n • Capacitor-discharge ignition systems with a movable trigger plate\n\u003c\/p\u003e\n\u003cp\u003e\n \u003cbr\u003e\n\u003c\/p\u003e\n\u003cp\u003e\n Verified catalogue families include:\n\u003c\/p\u003e\n\u003cp\u003e\n \u003cbr\u003e\n\u003c\/p\u003e\n\u003cp\u003e\n • Mercury 402 serial-number-controlled applications\n\u003c\/p\u003e\n\u003cp\u003e\n • Mercury 40HP two-cylinder applications\n\u003c\/p\u003e\n\u003cp\u003e\n • United States, Canadian, Australian and European serial ranges listed for the 402 \/ 40HP family\n\u003c\/p\u003e\n\u003cp\u003e\n \u003cbr\u003e\n\u003c\/p\u003e\n\u003cp\u003e\n Important fitment note:\n\u003c\/p\u003e\n\u003cp\u003e\n \u003cbr\u003e\n\u003c\/p\u003e\n\u003cp\u003e\n • Confirm that the engine is the two-cylinder 40HP or 402 design.\n\u003c\/p\u003e\n\u003cp\u003e\n • Mercury also produced three- and four-cylinder 40HP engines that use different triggers.\n\u003c\/p\u003e\n\u003cp\u003e\n • Compare the wire colours, connector terminals, linkage arm and mounting diameter.\n\u003c\/p\u003e\n\u003cp\u003e\n • Switchbox, stator, flywheel and mounting hardware are included only when shown or stated.\n\u003c\/p\u003e\n\u003cp\u003e\n \u003cbr\u003e\n\u003c\/p\u003e\n\u003cp\u003e\n 🔌 Function\n\u003c\/p\u003e\n\u003cp\u003e\n \u003cbr\u003e\n\u003c\/p\u003e\n\u003cp\u003e\n Trigger coils produce electrical pulses as the flywheel magnets pass over the assembly.\n\u003c\/p\u003e\n\u003cp\u003e\n \u003cbr\u003e\n\u003c\/p\u003e\n\u003cp\u003e\n The switchbox uses these pulses to discharge the ignition coils at the correct crankshaft position. Rotation of the trigger plate advances ignition timing as the throttle is opened.\n\u003c\/p\u003e\n\u003cp\u003e\n \u003cbr\u003e\n\u003c\/p\u003e\n\u003cp\u003e\n Common signs of trigger failure:\n\u003c\/p\u003e\n\u003cp\u003e\n \u003cbr\u003e\n\u003c\/p\u003e\n\u003cp\u003e\n • No spark on one or both cylinders\n\u003c\/p\u003e\n\u003cp\u003e\n • Intermittent spark\n\u003c\/p\u003e\n\u003cp\u003e\n • Spark disappears as the engine becomes warm\n\u003c\/p\u003e\n\u003cp\u003e\n • Difficult starting\n\u003c\/p\u003e\n\u003cp\u003e\n • Engine backfires\n\u003c\/p\u003e\n\u003cp\u003e\n • Misfire during acceleration\n\u003c\/p\u003e\n\u003cp\u003e\n • Engine will not reach maximum spark advance\n\u003c\/p\u003e\n\u003cp\u003e\n • Cracked or brittle trigger wiring\n\u003c\/p\u003e\n\u003cp\u003e\n • Trigger plate binds or does not return to idle\n\u003c\/p\u003e\n\u003cp\u003e\n • Resistance or peak output is outside specification\n\u003c\/p\u003e\n\u003cp\u003e\n \u003cbr\u003e\n\u003c\/p\u003e\n\u003cp\u003e\n Recommended checks before installation:\n\u003c\/p\u003e\n\u003cp\u003e\n \u003cbr\u003e\n\u003c\/p\u003e\n\u003cp\u003e\n • Confirm 4731A6 or 4731A8 on the original assembly\n\u003c\/p\u003e\n\u003cp\u003e\n • Compare the linkage arm and wire terminals\n\u003c\/p\u003e\n\u003cp\u003e\n • Measure trigger resistance\n\u003c\/p\u003e\n\u003cp\u003e\n • Check trigger peak output where specified\n\u003c\/p\u003e\n\u003cp\u003e\n • Inspect the flywheel magnets and key\n\u003c\/p\u003e\n\u003cp\u003e\n • Test the switchbox, stator and ignition coils\n\u003c\/p\u003e\n\u003cp\u003e\n • Confirm free trigger-plate movement\n\u003c\/p\u003e\n\u003cp\u003e\n • Set ignition timing and throttle synchronisation after installation\n\u003c\/p\u003e\n\u003cp\u003e\n \u003cbr\u003e\n\u003c\/p\u003e\n\u003cp\u003e\n 📦 Condition\n\u003c\/p\u003e\n\u003cp\u003e\n \u003cbr\u003e\n\u003c\/p\u003e\n\u003cp\u003e\n • Genuine Mercury or Mariner used part\n\u003c\/p\u003e\n\u003cp\u003e\n • Pre-owned electrical component\n\u003c\/p\u003e\n\u003cp\u003e\n • Wire ageing, marks and light oxidation may be present\n\u003c\/p\u003e\n\u003cp\u003e\n • Electrical testing before installation is strongly recommended\n\u003c\/p\u003e\n\u003cp\u003e\n • Included linkage and hardware are limited to those shown or described\n\u003c\/p\u003e\n\u003cp\u003e\n • Supplied in protective or equivalent packaging\n\u003c\/p\u003e\n","brand":"Sawley's Auto and Marine","offers":[{"title":"Default Title","offer_id":53392298049828,"sku":"R028513","price":40.0,"currency_code":"AUD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0994\/8115\/7924\/files\/original_98253bce-d587-4101-a3a1-a379da8b95f5.jpg?v=1777261257","url":"https:\/\/www.sawleysautoandmarine.com.au\/products\/4731a6-4731a8-mercury-trigger-genuine-used-part","provider":"Sawley's Auto and Marine","version":"1.0","type":"link"}