The CDI Electronics 174-9610A18 stator and regulator kit is an integrated ignition and charging system upgrade for Mercury and Mariner 2.0-liter, 2.5-liter and late-model 2.4-liter V6 outboards.
Specifically designed to replace Mercury’s 40-amp stator and single or dual-voltage regulator setups, this system resolves key electrical weaknesses found in earlier OEM configurations. It delivers consistent current output across the RPM range while maintaining compatibility with Mercury's ignition and charging harness architecture.
This kit is engineered as a direct replacement for Mercury OEM part numbers 398-9610A18, 84-85532, and 84-85532A1. These OEM components were originally installed on V6 models from the 1989 through the early 2000s that utilized either a single water-cooled voltage regulator or dual air-cooled regulators. By combining both the stator and regulator(s) into one engineered package, CDI simplifies electrical servicing while improving long-term reliability.
System Design and Functional Characteristics
Mercury’s original 40-amp stator system on 2.0L, 2.5L, and late 2.4L engines used a fixed coil alternator positioned beneath the flywheel. The stator outputted alternating current through two or four yellow leads (depending on configuration) and was paired to either a water-cooled single regulator or dual air-cooled regulator modules. These systems fed power to the engine's ignition switchboxes or ECM and charged the onboard battery via a full-wave rectified DC circuit.
The CDI 174-9610A18 kit includes a high-output stator featuring modern epoxy encapsulated windings, designed for superior heat resistance, vibration durability, and magnetic consistency. It also includes dual solid-state voltage regulators engineered to stabilize charging voltage while minimizing the thermal cycling that typically degrades OEM-style regulators.
The system supports up to 40 amps of output, sufficient for multi-accessory electrical loads common in bass boats, offshore vessels, and performance hulls powered by V6 two-stroke Mercury outboards.
CDI Electronics 174-9610A18 Stator and Regulator Kit
The regulator modules are equipped with updated circuitry to prevent over-voltage conditions, protect connected ignition modules, and maintain charging stability even under high RPM or full accessory draw. Unlike the original water-cooled regulator—known to suffer from internal corrosion, seal failure, and output drift—the CDI regulators are sealed and air-cooled, eliminating reliance on the outboard cooling circuit and improving longevity in saltwater environments.
Engine Compatibility and Application Range
The 174-9610A18 kit is compatible with Mercury and Mariner 2.0, 2.4, and 2.5 Liter V6 outboards factory-equipped with the 16-pole flywheel and 40-amp stator system. Supported engines include the Mercury 135HP, 150 HP, XR6, XRi, 175 HP, 200 HP, 200 EFI, 225 EFI, and Pro Max V6 engines produced from approximately 1989 through the early 2000s. These models used either single or dual-regulator charging architectures depending on power output and electrical load requirements.
The kit is suited for both carbureted and EFI V6 platforms, including models with 40-amp alternators and external ignition modules. It is not compatible with earlier 9- or 16-amp charging systems, nor with later 3.0L V6 engines or four-stroke models, which use distinct stator/regulator designs.
By maintaining wiring harness compatibility and matching Mercury’s original power curves and frequency profiles, the 174-9610A18 allows seamless replacement without the need for reconfiguring ignition or accessory systems.
Its installation is suitable for both production-level service work and performance rebuilds where clean voltage and robust charging are critical.
Technical Performance and Service Considerations
The CDI stator features improved coil alignment and resin encapsulation for enhanced thermal performance and minimized output drift. These upgrades directly address one of the most common points of failure in OEM Mercury systems: stator insulation breakdown under prolonged heat exposure.
The included regulators are rated for continuous use under full-field conditions and can withstand electrical surge, thermal cycling, and vibration far beyond the tolerance of legacy parts.
Installers should verify flywheel compatibility, inspect harness condition, and check regulator ground paths to ensure stable system integration. When upgrading from a single-regulator system, the kit simplifies conversion by eliminating the water-cooling requirement and replacing it with a dual air-cooled system built to modern efficiency standards.
Once installed, the stator delivers predictable AC voltage output across idle, cruise, and WOT ranges, ensuring reliable spark timing and battery charging across operational cycles. The dual-regulator setup maintains DC output with low ripple and voltage regulation within the optimal range for switchbox or ECM input protection.
Built for technical accuracy, service longevity, and seamless integration, the 174-9610A18 is an optimal choice for maintaining the electrical integrity of high-output Mercury V6 platforms operating in both recreational and professional marine environments.
Contact Mike Hill at +1-714-697-1716 or email mike@buckshotracing77.com for technical support