Touch and go
New Member
1989 Sundancer 300 5.7 260hp Mercruiser. I have a low end knock and white smoke coming from the breather hoses attached to the valve covers. I can also hear some blow by. Any thoughts?
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Engine trouble
- Thread starter Touch and go
- Start date
300SR
New Member
- Mar 3, 2011
- 264
- Boat Info
- 1989 340 Sundancer All Raymarine electronics
- Engines
- Twin GM 454's
Look for a new motor....................
tbirdvet
Active Member
- Sep 24, 2009
- 1,568
- Boat Info
- Previous boat: 2008 330 Sundancer
Vetus Bow Thruster
Kohler Gen.
- Engines
- Twin 496 MAG, 375HP Bravo III,
Low end knock probably a bearing. Blow by means time for rings. How many hours on this engine? Probably time for major rebuild or new engine like 300SR said.
Touch and go
New Member
Supposedly only 300 hours on engine. I bought the boat in March so I can't verify that as being the case.
Dick270da
New Member
The incorrect weight oil can cause the same problems. Have you changed it? Do you know what kind of oil is in it? You can also "fix" some of these problems by going to a different weight oil, for example if a 25w50 weight oil exhibits these problems, a straight 30w may buy you some time.
