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.Watch 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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