ARCO IG027 Yamaha 55-90HP Outboard Ignition Coil

The ARCO IG027 ignition coil is specified for selected Yamaha 90HP and C55 outboards from the 1980s and early 1990s. The supplier lists Yamaha 90 applications from 1984-1988 and C55 models from 1989-1994. Those older engines may have been repaired several times over their service life, making part-number verification especially important. The replacement is intended to restore the original coil function without altering the factory ignition arrangement.

Yamaha 697-85570-10, 697-85570-11-00, and 697-85570-10-00 are listed as OEM references. Mercury 97077M and 81549M are also included, along with Sierra 18-5111 and CDI Electronics 187-9711. These cross references help identify the correct coil even if the engine is currently fitted with an aftermarket part. Compare the physical connection and mounting points to the removed component before installation.

Inspect the plug lead, primary connection, grounds, and nearby wiring for age-related corrosion or damaged insulation. Older ignition systems often benefit from correcting poor terminals at the same time the coil is replaced. ARCO lists 12 months of materials-and-workmanship coverage for leisure use and 90 days for commercial or racing service. Confirm stable ignition and clean acceleration after the repair is complete.

• Specified for selected Yamaha 90HP and C55 applications
• Cross-references Yamaha and Mercury coil numbers
• Also cross-references Sierra 18-5111
• Also cross-references CDI Electronics 187-9711

For more Yamaha ignition coils and service components for older outboards, Browse more Engine Controls & Ignition for related replacement and service components.