The Race Kilovac Relay from Buckshot Racing #77 is a 500-amp marine contactor engineered to replace traditional starter and trim solenoids used on Mercury, Yamaha, and OMC outboards. Designed for harsh marine environments, this relay provides more reliable switching and higher current capacity than conventional OEM solenoids commonly used on performance boats.
The relay uses the same mounting footprint as the common Mercury black and brown solenoids, allowing quick installation with minimal wiring changes. Although slightly taller than the original parts, the bolt pattern and connections remain familiar, making it an easy upgrade for Mercury V6 two-stroke outboards and high-performance marine electrical systems.
With a simple two-wire activation circuit, tinned copper quick-connect terminals, and sealed construction, the Buckshot Racing #77 Race Kilovac Relay eliminates common problems such as voltage drop, contact welding, and solenoid chatter.
Built for High-Performance Marine Applications
This relay is designed for high-current marine systems used in performance boats and race applications. It is commonly installed to control starter motors, trim and tilt pumps, hydraulic jack plates, lift pumps, and auxiliary electrical circuits.
It is widely used across performance boating and racing classes including F1H2O, IHRA F1, SST-120, F2, F200, SST-45, outboard drag racing, river racing, and offshore performance boats.
The relay supports Mercury Racing engines from 135 HP through 300 Drag, including the 2.0L, 2.4L, and 2.5L V6 platforms, as well as many Yamaha and OMC V-block race engines. Its 500-amp switching capacity ensures stable power delivery during heavy starter loads or hydraulic pump surges.
Advanced Electrical Design
Unlike typical automotive solenoids, the Race Kilovac Relay is hermetically sealed and rated IP67, protecting internal components from moisture, salt spray, and vibration. The relay is built to aerospace-grade standards and tested for over 30,000 switching cycles in high-load conditions.
Internally, silver-tungsten contacts and ceramic arc suppression chambers provide clean electrical switching under high current loads, reducing contact wear and preventing welded contacts often seen in conventional marine solenoids.
An integrated electronic economizer circuit reduces coil power after engagement. The relay initially energizes at full power, then drops to a holding draw of approximately 1.7 watts, minimizing heat buildup and preventing voltage dips that can affect ignition systems or ECU electronics.
The relay is compatible with 12-volt, 24-volt, and 36-volt marine electrical systems, covering everything from lightweight race boats to large offshore performance setups.
Replacement for Mercury and ARCO Solenoids
The Buckshot Racing #77 Race Kilovac Relay replaces many legacy Mercury Marine, Quicksilver, and ARCO starter and trim solenoids, including part numbers F460917-1, 15857, 18-5815, 61053, 68258, 68258A4, 68258B4, 72370, 76545, 76545T, 853654A1, 853654B1, and 9-15111.
It also replaces Mercury service numbers including 89-68258A4, 89-76528T1, 89-817109A1, 89-817109A2, 89-817109A3, 89-850187T1 (now 8M0185146), and 89-8M0185149.
These solenoids were widely used on Mercury two-stroke outboards, performance V6 engines, and sterndrive systems, but many suffer from corrosion, voltage loss, and contact failure after prolonged marine use.
A Proven Upgrade for Performance Boats
For racing teams, marine technicians, and performance boat owners, electrical reliability is critical. The Buckshot Racing #77 500-amp Race Kilovac Relay delivers stable switching and long service life under demanding marine conditions.
Whether installed on F1 tunnel boats, outboard drag racing engines, bass boats, or offshore performance hulls, this relay provides dependable control for starter circuits, trim systems, jack plates, and hydraulic pumps.
For anyone still running legacy solenoids such as 89-68258A4, 76545T, 18-5815, or the 89-817109A series, the Buckshot Racing #77 Race Kilovac Relay provides a modern high-current upgrade built for high-performance marine electrical systems.
Contact Mike at 714-697-1716 or mike@buckshotracing77.com for technical support.