The Race Kilovac Relay from Buckshot Racing #77 is a high-performance, 500-amp marine contactor designed as a direct replacement for OEM Mercury, Yamaha, and OMC solenoids.
 
It matches the footprint of the familiar black and brown Mercury solenoids—just slightly taller—so installation is similar, but the performance difference is improved. With its 2-wire design, tinned copper quick-connect terminals, and bolt pattern identical to OEM parts, it drops right in while eliminating the weaknesses of traditional solenoids.
 
Wide Application in Racing Classes
This relay is built for the fiercest marine competitions: F1H2O, US F1, SST-120, F2, F200, SST-45, drag racing, river racing, and offshore performance boats. Whether driving trim, lift, tilt, jack plate, or starter systems, it supplies clean power without chatter, welds, or ECU voltage drops.
 
From Mercury Racing 135HP through 300 Drag, including the 2.0L, 2.4L, and 2.5L outboard families, to Yamaha and OMC V-block race motors, this 500-amp upgrade is engineered to deliver consistent results across the most demanding platforms.
 
Engineering Advantages
Unlike generic automotive or ARCO solenoids, this unit is hermetically sealed, IP67 rated, and built to aerospace and defense specifications, with a tested life of over 30,000 heavy-duty cycles.
 
The silver–tungsten contacts and ceramic arc-suppression chambers ensure clean switching even when hydraulic pumps surge to 80 amps or starter loads kick back past 200 amps.
 
An advanced electronic economizer optimizes coil power draw—engaging with full force, then dropping hold power to just 1.7 watts—preventing overheating, reducing current loss, and eliminating the ECU resets common to older OEM parts.
 
With support for 12V, 24V, and 36V systems, it covers the full spectrum of high-performance electrical setups, from lightweight SST catamarans to big-block offshore hulls.
 
Replacement for OEM Solenoids
The Race Kilovac Relay from Buckshot Racing #77 replaces a long list of legacy Mercury/Quicksilver and ARCO solenoid part numbers, including F460917-1, 15857, 18-5815, 61053, 68258, 68258A4, 68258B4, 72370, 76545, 76545T, 853654A1, 853654B1, 9-15111, OEM 89-68258A4, and OEM RACE 89-76528T1.
 
It also supersedes later Mercury/Quicksilver references like 89-817109A1/A2/A3, 89-850187T1 (now 8M0185146), and 89-8M0185149.
 
These were standard starter and trim solenoids on legacy two-stroke outboards and sterndrive platforms, but none match the endurance or current handling of the Buckshot Racing 77 relay.
 
For professionals in F1H2O racing, outboard drag racing, and high-output performance boating, the difference is clear. OEM-style solenoids pit, corrode, and weld shut after weeks in saltwater and vibration. The Buckshot Racing #77 500A Race Kilovac Relay endures season after season, delivering crisp pump response, rock-solid starts, and proven reliability under hull-slamming abuse.
 
This isn’t just a solenoid—it’s a race-grade contactor engineered for victory. If your electrical system still relies on Mercury or ARCO solenoids like 89-68258A4, 76545T, 18-5815, or 89-817109A-series, the Buckshot Racing #77 Race Kilovac Relay is the definitive upgrade. One install, one solution—built for trim and lift pump precision, starter reliability, and the unforgiving demands of competitive marine racing.
 
Contact Mike at 714-697-1716 or mike@buckshotracing77.com for technical support.