Sailing Catalpavideo
Save $$$ Servicing Your Own 15HP Mercury Outboard (4-Stroke) Episode 494
June 7, 2026 · 25 min · 6K views
Man drains oil from outboard motor into container on sailboat
What this video covers
A 15 HP Mercury four-stroke outboard gets a break-in service before an offshore Pacific passage, with the work performed by Lee aboard Catalpa.▶ 0:00 The service covers propeller removal, spline greasing, and inspection for fishing line near the prop shaft seal — a common failure point that allows gearbox oil to escape.▶ 1:54 Gearbox oil is drained and refilled from the bottom drain hole using a hand pump until fluid exits the top port; the fill quantity works out to roughly 500 ml of SAE 90 weight gear oil.▶ 5:47 The lower unit leg is dropped by removing four bolts and the gear shift selector nut to expose the impeller housing; the impeller is inspected but not replaced because the motor is new, with replacement scheduled at the 100-hour service.▶ 9:33 Engine oil is drained with the motor tilted up, the oil filter replaced with a genuine Mercury unit (West Marine stocks both Mercury and Quicksilver), and spark plugs swapped out.▶ 16:03 Greasing points on the tiller pivot are serviced monthly given daily tender use.▶ 14:17 Four zinc anodes are identified and checked.▶ 14:09 All consumables and tools came from West Marine, the episode's sponsor.▶ 0:09
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