500 Hour Service-gctid809721

[Glasply1]

My 2007 5.7L 350 mercruiser is approaching 500 hours. Motor has run extremely well to date with great and consistent oil pressure and engine temps and very little oil burn. Faithfully maintained every 100 hours. Anything special required at 500? Anything to watch out for to indicate an imminent problem?

[Pcpete]

Exhaust manifolds and risers inspected, that's an inside job, all hoses and bellows, engine alignment, raw water pump.

IMO, you should be changing your oil at least annually rather than hours based. You appear to be only averaging 50 hours a year and the oil is degrading based on time it's in the engine more than use. Just an observation, others will probably disagree with the significance.

[aknurse]

+1 on the annual oil changes. At a minimum. Oil is cheap insurance.

[smitty477]

"Faithfully maintained every 100 hours. Anything special required at 500?"

It would depend a lot on what you do faithfully every 100 hours.

What is on that list?

[Glasply1]

I bought the boat sept '16 with 175 hours and have put on nearly 325 since then (and covered ~4,800 miles). I replaced all hoses when I bought it. Changed out manifolds and risers at 250 hours (looked fine, but cheap insurance based on 10 year old motor). I have put new bellows and water pump impeller at 350 hours. Boat also had outdrive off and serviced at 350. She fires up easy, runs strong and burns virtually no oil. Want to keep it that way! I agree an annual oil change is minimum requirement and techs seem to agree every 100 hours in use, but we're running hard virtually daily and wonder what else to think about.