Check engine and lower-unit oil color monthly

Oil color tells you more than the hour meter — milky oil means water intrusion; metallic glitter means internal wear.

Book professional help More Engine Maintenance tips

Why this matters

Oil color tells you more than the hour meter — milky oil means water intrusion; metallic glitter means internal wear.

No regrets: Never ignore milky gear lube. Water in the lower unit destroys bearings fast.

When DIY is not enough

Milky oil, metal on the plug, or a sudden drop in level needs diagnosis before you run again. Our 50- and 100-hour services include fluid inspection and documented photos.

DIY steps

With the engine off and trimmed appropriately, check the upper crankcase dipstick or sight window.
Inspect lower-unit lube at the vent/fill screw — it should be amber to light brown, not foamy or gray.
Smell and look for metal particles on the magnetic drain plug if equipped.
Photograph anything unusual before your next run.

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Common questions

Check engine and lower-unit oil color monthly

Oil color tells you more than the hour meter — milky oil means water intrusion; metallic glitter means internal wear. Never ignore milky gear lube. Water in the lower unit destroys bearings fast.

When should I call a professional instead?

Milky oil, metal on the plug, or a sudden drop in level needs diagnosis before you run again. Our 50- and 100-hour services include fluid inspection and documented photos.