• Mobile App For Android Now Online!

    Download it here. The app is searchable in the Google Play Store under Sailboat Owners.

    Sorry iPhone/iPad users, we are still waiting on Apple. :(

    Click the X in the upper right corner to make this go away

Yanmar YSM8G -engine racing w/ lots of smoke

Aug 24, 2014
140
Aphrodite 101 148 Coeur d Alene ID
It was running under power fine when suddenly the engine began racing and pouring out smoke. I shut it off but took a minute to finally shut down. After a few minutes started it back up and seems to run fine. Any thoughts on what might have caused this?
 

19thol

.
May 2, 2014
110
Hunter 30 St.Petersburg, Fl
sounds like it was somehow sucking oil out of the crankcase and running on that.
 
May 24, 2004
6,752
CC 30 South Florida
Just needed a soft reboot. No really, some obstruction interrupted the flow of fuel and your engine switched to sucking engine oil out of the crankcase through seemingly well worn piston rings.. There is a long list of possible causes from dirty fuel tank, clogged fuel filters, water in the fuel, sticking high pressure pump, etc. I would start by replacing the primary and secondary fuel filters. A runaway diesel can be catastrophic; blocking the air intake tube with a large rag will quickly shut the engine off. Try to locate the cause, because this will tend to happen again.
 
  • Like
Likes: FastOlson
Aug 24, 2014
140
Aphrodite 101 148 Coeur d Alene ID
Just needed a soft reboot. No really, some obstruction interrupted the flow of fuel and your engine switched to sucking engine oil out of the crankcase through seemingly well worn piston rings.. There is a long list of possible causes from dirty fuel tank, clogged fuel filters, water in the fuel, sticking high pressure pump, etc. I would start by replacing the primary and secondary fuel filters. A runaway diesel can be catastrophic; blocking the air intake tube with a large rag will quickly shut the engine off. Try to locate the cause, because this will tend to happen again.
Thanks!
 
Jul 23, 2009
489
Beneteau 31 Oceanis Grand Lake, Oklahoma
Check the oil level. Is it where it should be?
If it's low it was likely running on the engine oil. This can sometimes happen when the oil is pushed out the crankcase vent and sucked into the air intake. Why does this happen? My guess is that the engine has lots of blow by due to worn rings or the oil was overfilled.
If the engine oil is high, it was either overfilled or the fuel is leaking into the oil. Oil contaminated with fuel is not good. You must find the source of the fuel and repair it and change the oil.
 
Aug 24, 2014
140
Aphrodite 101 148 Coeur d Alene ID
Check the oil level. Is it where it should be?
If it's low it was likely running on the engine oil. This can sometimes happen when the oil is pushed out the crankcase vent and sucked into the air intake. Why does this happen? My guess is that the engine has lots of blow by due to worn rings or the oil was overfilled.
If the engine oil is high, it was either overfilled or the fuel is leaking into the oil. Oil contaminated with fuel is not good. You must find the source of the fuel and repair it and change the oil.
tks
 

Boffin

.
Aug 30, 2010
80
yahama 25 Hong Kong
I have experienced this due to too much lub oil was filled. Then the engine racing with a lot of white smoke.I needed to plug the air intake to stop the engine. Taken out the excess oil and the engine resume normal. It is likely that the excessive oil affected the governer.
 
Aug 24, 2014
140
Aphrodite 101 148 Coeur d Alene ID
pretty sure it was a result of excess oil and an old tired engine. no idea of prior engine care but knowing the prior owner don't think much was done. seems run fine now just very hard to start which as others have pointed out may also be a sign of being tried. began using wd40 when cold starting. once it's warm it restarts fine. hope this gets me through the season. plan to change it out next winter.