ARCO Mercury 9-Tooth Replacement Outboard Starter

The ARCO 5360 is a 9-tooth replacement starter for Mercury and Mariner 40, 50, and 60 HP four-cylinder 4-stroke outboards. It replaces Mercury 50-859377T, 50-884044T, 50-888161T, and 50-893888T, along with Sierra 18-6435. The 9-tooth drive gear matches the original engagement with the flywheel on these engines.

These mid-size Mercury 4-strokes are common on pontoons, aluminum fishing boats, and small center consoles, and the starter is one of the parts most likely to wear over the years. Slow cranking, grinding, or a single click when you turn the key can all point to the starter or to the power feeding it. Test the battery and cables first so you replace the part that actually failed. A starter that spins without turning the engine usually points to a worn drive gear, while a repeated click with full battery voltage often means a failed solenoid.

ARCO induction hardens the shaft at the bearing surfaces and epoxy powder coats the housing. Each motor is tested at five load levels and must meet or exceed original equipment performance before it ships. Disconnect the battery before removal, clean the cable ends, and tighten the mounting bolts evenly. Check the flywheel ring gear for chipped teeth while the starter is off, since damaged teeth will wear a new drive gear quickly. Browse the rest of our marine starters.

• Fits Mercury/Mariner 40, 50, 60 HP 4-cylinder 4-stroke
• 9-tooth drive gear
• Replaces Mercury 50-859377T and 50-884044T
• Tested at five load levels