Mercury MerCruiser Quicksilver Ignition Coil 8M0044991

Mercury MerCruiser Quicksilver Ignition Coil 8M0044991

The Mercury MerCruiser Quicksilver 8M0044991 is a genuine OEM dual-output ignition coil for select Mercury four-stroke outboards and MerCruiser electronic ignition systems. It converts battery voltage into the high-voltage output needed to fire the spark plugs. On applicable MerCruiser 4.5L MPI V6 engines, three coils are used per engine.

Compatible Applications

• MerCruiser 4.5L MPI 200 Alpha
• MerCruiser 4.5L MPI 200 Bravo
• MerCruiser 4.5L MPI 200 Alpha and Bravo EC
• MerCruiser 4.5L MPI 250 Alpha
• MerCruiser 4.5L MPI 250 Bravo
• MerCruiser 4.5L MPI 250 Alpha and Bravo EC
• Select Mercury four-stroke outboards in the 4060 HP, 75115 HP, 135150 HP, 3.4L V6 175200 HP, and 4.6L V8 200300 HP families

Ignition components can change within the same horsepower and engine family. Confirm 8M0044991 against the engine serial number and the applicable electrical diagram before ordering, especially near a production or emissions-system change.

Part Details

• Brand: Mercury MerCruiser Quicksilver
• OEM part number: 8M0044991
• Mercury service reference: 300-8M0044991
• Condensed catalog reference: 3008M0044991
• Product type: Dual-output ignition coil
• System: Engine ignition and electrical
• MerCruiser diagram position: Electrical Components, Starter, Alternator and Coil Bracket
• Diagram quantity: Three coils per applicable MerCruiser 4.5L V6 engine
• Current status: 8M0044991 remains a current Mercury Quicksilver service part

Key Features

• Genuine OEM dual-output ignition coil
• Designed for reliable high-voltage spark delivery in marine ignition systems
• Direct identification by OEM part number 8M0044991
• Earlier or cross-referenced number: 8M0029482

When Replacement May Be Needed

Replacement may be appropriate when diagnosis identifies an intermittent or persistent misfire, weak or missing spark, difficult starting, rough running, hesitation, loss of power under load, or a cylinder pair that is not firing correctly. Inspect for cracking, heat damage, corrosion, damaged terminals, and connector problems.

Similar symptoms can also come from spark plugs, plug wires, wiring, grounds, connectors, or ECM-related faults. Diagnose the ignition system before replacing the coil.

Installation Notes

Disconnect battery power before servicing ignition-system wiring. Compare the replacement with the original 8M0044991 unit and inspect the connectors, high-tension leads, mounting hardware, and coil bracket. Verify routing and connections against the applicable electrical diagram before restoring power.

Technical FAQ

Is this a single-output coil?
No. 8M0044991 is a dual-output ignition coil.

How many coils does a MerCruiser 4.5L V6 use?
Applicable MerCruiser 4.5L V6 diagrams show three 8M0044991 coils per engine.

Does 8M0044991 replace 8M0029482?
8M0029482 is an earlier or cross-referenced Mercury ignition-coil number. Current catalog references identify 8M0044991 as the current service part.

Can horsepower alone confirm fitment?
No. Verify the exact engine model, drive or outboard configuration, serial number, and electrical diagram before ordering.

View the MerCruiser 4.5L MPI 250 electrical components, starter, alternator and coil bracket diagram.

Parts Desk Insights

Best use: Use this coil when the engine’s electrical diagram identifies Mercury 8M0044991 for the applicable MerCruiser or Mercury four-stroke application.

Common mistake: A misfire is not proof that the coil has failed. Check spark plugs, plug wires, connectors, grounds, and related ignition wiring before replacing the coil.

Fitment guidance: If you are servicing a MerCruiser 4.5L MPI V6, remember that three dual-output coils are used and one failed coil can affect more than one cylinder. Match 8M0044991 to the engine serial number before ordering.