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The NEWHOW 2-Pack Ignition Coil 18-5186 delivers two direct aftermarket replacements for Mercury, Mariner, and Force 2-stroke outboards (6-150HP, late 1970s-mid 1990s). Each coil replaces Sierra 18-5186 and crosses 398-9614, 339-832757A4, 339-7370A13 across their full A1-A500 suffix range. Specs: 2-wire spade (primary + ground), 12V, oil-filled canister, ~15kV secondary, 1-2Ω primary. Coverage spans the entire 2-cylinder 2-stroke family — including Jet models. Because Mercury gated fitment to serial number prefix + coil stamp, not HP alone (a 1992 60HP with serial 0G760299-up uses 18-5186; a 1982 60HP with serial 0D283222 uses an earlier variant; a 1998 75HP 3-cyl uses a different coil), requires structured fitment in Part Finder—that data is uploaded via ACES CSV on this . Always match your old coil stamp 18-5186 or 398-9614 and confirm 2-wire + serial range before purchase. This SKU is 2-wire 12V only, not 3-pin, not 4-stroke EFI. On 2-cylinder engines this 2-pack = complete matched set; on 3-cylinder engines use 3 coils. Replace when misfire or no-spark occurs; reuse existing plug leads unless high-resistance.
2-Pack 12V Canister Ignition Coils — Replaces 339-7370A13 / Sierra 18-5186 Set of two direct aftermarket oil-filled ignition coils for Mercury/Force/Chrysler 2-stroke outboards. Replaces Mercury 339-7370A13, 339-7370B13, 339-832757A4, 339-832757B4, 338-4774A1, 338-4995A1/A2, 339-7370A2/A6/A8/A16/A17/A19/A23, 339-832757A3, 339-7370A23, F718475 and crosses Sierra 18-5186 / 18-5186D, Mallory 9-23200, Recmar REC300-08309, 8M0219430, 8M0230859. Specs: 12V, ~1.5-2.0Ω primary, ~8-10kΩ secondary, oil-filled steel canister, 2 blade terminals + 1 high-tension tower. Match your old coil stamp before ordering. Not a CDM module (827509A10), not a stator, not a trigger plate.
Fits Mercury/Mariner 40/70/90/115/150/200HP 2-Stroke & Force 40-90HP Engineered for the most common Mercury/Mariner 2-stroke configurations: 40HP 2-cyl, 70/90HP 3-cyl, 115HP 4-cyl, 150/200HP V6, plus Force/Chrysler 40/50/70/90HP (S/N E000001-E138599) and Sport Jet 120/150HP.
Fixes Weak Spark, Hard Cold Start & Mid-RPM Misfire Resolves canister-coil failures: orange spark instead of blue-white, 10+ pulls to cold-start, misfire above 3000rpm, or engine dies when choke is released. Internal oil dries or windings open over time. New coil restores 25-30kV output. Test old coil: primary 1.5-2Ω (between blades), secondary 8-10kΩ (blade to tower); open or short = dead coil.
Wire-In to Harness in 15 Minutes Disconnect battery, locate coil (starboard side near flywheel), unplug 2 blade wires, remove high-tension lead from tower, unbolt coil bracket, mount new coil, torque to 35 in-lb, reconnect blades, route plug wire to correct cylinder. Critical: use dielectric grease on tower; verify blade polarity (reverse = weak spark). Reuse or replace plug wires (not included).
339-7370A13 Canister Coil ≠ 827509A10 CDM Module — Confirm 2-Blade + Tower This is the traditional oil-filled canister with 2 blade terminals + 1 high-tension tower for pre-CDM Mercury/Force 2-stroke (1976-2006). The 827509A10 4-pin CDM has NO tower and 4 pins — completely different ignition system. Photo old coil: 339-7370A13 or Sierra 18-5186 stamp + cylindrical can + 2 blades + 1 tower = exact fit. 4-pin epoxy block = wrong generation.
