NEWHOW Ignition Coil 339-7370A13 2-Pack 12V Oil-Filled Canister for Mercury/Mariner - OEM Fit

NEWHOW 2-Pack Ignition Coil 339-7370A13 is a direct-fit, oil-filled 12V canister coil set that replaces Mercury/Mariner OEM canister coils to restore strong spark and reliable starting on compatible 2-stroke outboards.

These two replacement coils are engineered for pre-CDM Mercury/Force 2-stroke ignition systems and cross-reference Sierra 18-5186 and several other aftermarket numbers. Each canister includes two blade terminals and one high-tension tower; they are oil-filled steel housings designed to match original mounting and electrical characteristics. Use the coil code on your old part to confirm fit before ordering.

How will these coils affect my engine’s starting and spark?

Worn or failing canister coils often produce a weak orange spark, require many pulls or excessive cranking to start, or cause misfires at mid to high RPM. Installing fresh NEWHOW coils restores proper primary and secondary resistance ranges and returns reliable high-voltage output for normal ignition performance.

• Restores expected 25–30 kV secondary output under load
• Primary resistance: ~1.5–2.0 Ω between blade terminals
• Secondary resistance: ~8–10 kΩ blade to tower
• Fixes hard cold starts, misfire above ~3000 rpm, and weak-spark symptoms

Which engines and serial ranges does this 2-pack fit?

These coils are made to match the common Mercury/Mariner 2-stroke canister ignition layouts. They suit 2-cylinder, 3-cylinder, 4-cylinder and V6 configurations where the original coil is the oil-filled canister with two blades plus a tower.

• Fits Mercury/Mariner 40–200 HP 2-stroke layouts (40, 70, 90, 115, 150, 200 HP)
• Compatible with Force/Chrysler 40–90 HP (S/N E000001–E138599) and Sport Jet 120/150 HP
• Crosses to Sierra 18-5186 and several listed aftermarket numbers
• Not compatible with CDM 4-pin epoxy modules (e.g., 827509A10)

What should I check before ordering and installing these coils?

Confirm the old coil style and stamp: the correct part is a cylindrical oil-filled canister stamped with part numbers like 339-7370A13 or Sierra 18-5186 and has two blade terminals plus a high-tension tower. If your current ignition uses a 4-pin CDM epoxy block with no tower, this canister coil is not compatible.

• Verify the old coil stamp and physical shape before purchase
• Test old coil: primary ~1.5–2 Ω, secondary ~8–10 kΩ; open/short = replace
• Disconnect battery and mark blade polarity before swapping
• Use dielectric grease on the tower and torque mounting bolts to ~35 in‑lb

How difficult is installation and what tools or parts are required?

Installation is straightforward for anyone comfortable working on small outboard ignition systems and typically takes about 15 minutes per coil. You will remove the old coil, transfer or replace plug wires, and mount the new canister, taking care with blade polarity and routing to avoid weak spark from reversed connections.

• Typical steps: disconnect battery, unplug blades, remove HT lead, unbolt old coil, mount new coil, reconnect
• Recommended: dielectric grease, basic hand tools, torque wrench/driver for 35 in‑lb
• Plug wires are not included — reuse or replace if worn
• Do not substitute for CDM module, stator, or trigger plate

Who is this replacement coil set for? NEWHOW’s 2-pack is aimed at boat owners, mechanics, and mariners who need an affordable aftermarket replacement for failing oil-filled canister ignition coils on compatible Mercury/Mariner and Force 2-stroke outboards. Choose this set if your engine shows weak spark or starting troubles and your existing coil is the two-blade plus tower style (pre-CDM). Always match part stamps and physical appearance to guarantee fit and reliable operation.