smoke/smell

[nickgolf101]

Hey guys!
So I have a 2002 2400scr w/ a 5.7L mercruiser I/O. Last night when I started it after sitting for a couple hours there was a steam like smoke coming from the engine and the smell of gas/oil burning was extremely strong. I took it out for a spin and it seemed to stop. it seemed to be running very rich... but I never seem the steam/smoke before?? I checked the oil when i got back to the dock and it looked ok.

Is this something I should be concerned about?

[mmwjr]

YES!

What color was the smoke? White = water, Black = gas, Blue = oil and where was it coming from? Engine compartment, out back of boat, ...

Oil or water could be leaking gaskets. Gas is a fuel system issue; carb, gas line, ..

Engine temp ok?

[nickgolf101]

Engine temp is fine stays at 180... it was coming from the back of boat exhaust. It was night time so I believe the color was blue.

[CountryME]

Pretty common for 4.3l and 5.7l chevy engines. The valve guides and valve seals wear over time. A few drops of oil will drip through the valves and you will get a puff of blue smoke that will smell like burning oil at start up after sitting a few hours or over night. No worries, this will not damage the engine and is just a sign of age.

-JP

[mmwjr]

180 is a little high. Use a handheld IR test sensor to verify.

As country stated bad valve seals and guides will allow oil to leak past valves and result in a blue buff when starting

[nickgolf101]

So I started the boat today and it didn't smoke at all... but I did notice what looks like a little oil in the water near the out drive... thoughts????

[nickgolf101]

So I started the boat today and it didn't smoke at all... but I did notice what looks like a little oil in the water near the out drive... thoughts????

[mmwjr]

First thought would be gear lube but based on what you have been saying I am thinking gas or some engine oil that came past valves and the exhaust.

[nickgolf101]

Mike, it's funny you say gear lube because I just added some lube a few days ago... the reservoir was very low! Could that be the issue??

[mmwjr]

Well if the tube from the reservoir or the fitting at the transom is leaking it may allow lube to leak onto the engine and when the engine gets hot cause the smoke/smell. Not sure about the lube in the water this way unless the bildge pump dumped so overboard.

A leaking seal or the transom hose on the outside can be leaking lube into the water but this will not be tied to the smell/smoke issue.