On Sep 1, 10:21 pm, "aieo" wrote:
2001 Mercruiser 4.3L, low hous, runs well, strong and starts reliably.
Recently noticed a bit of blue smoke after start. Dissipates fast. Oil level
slightly above the full mark on dipstick?

Any clues as to why this is happening?

Even though it's low hrs, it's still almost 7 yr.s old, and probably
the valve seals are getting brittle. the valve seals are an umberella
shaped rubber compound seal that is located under the valve springs,
that keeps the oil from dripping down along the valves into the
cylinders. It's common with GM engines. Yes, you'll get that on the
initial start up, because a few drops of oil are being combusted. But
like you said, it dissipates quickly. Not really anything to worrry
about, but if you winterize the boat this winter, you might want to
see about having the valve seals replaced. It helps control the
obnoxious level.

; * )