[C320-list] Sudden blue smoke, Perkins M30

[P.F. Ross]

All,

We had been motoring yesterday at our normal 2600 RPM for about an hour
when suddenly the engine lost power, revs dropping down to 1800 or so.  At
that same instant I noticed smoke from the exhaust like I had never seen
before.  I throttled back, gave the admiral the wheel, went below, removed
engine covers and checked everything.  All appeared normal.

We were just about to enter a busy harbor, so not knowing what was going on
I decided to shut the engine down and called for a tow.  We were about 10
miles from home so decided to go back there.  Fortunately, winds were light
and seas were flat.

The week before I had changed both fuel filters and the fresh water
impeller, preparing for a cruise.  Fuel tank was topped up with the same
Shell brand terrestrial diesel I have used for the past 9 years.

I have owned the boat since new (1994) and the engine has 550 hours, the
majority of those accumulated since I moved the boat to SW FL in 2015.
Regular oil, filter and coolant changes are known since I have done them
all.

Today at my dock, the engine starts and seems to run ok, but still belching
clouds of what I would call blue smoke and is leaving a sheen on the
water.  It also has a peculiar smell, perhaps somewhat sweet.

So it seems like oil smoke, but for the life of me I cannot imagine what
failure would cause sudden oil burning.  I suppose a fuel injector could
suddenly malfunction (I have never messed with the injectors) but that
would seem to be black smoke.

I will try to find a diesel mechanic to come check it out next week but
thought I would see if anyone on here had an idea of what may be going on.

Thanks and regards,

Frank Ross
Beta Wave #206
Naples, FL