Blown head gasket?

[tinny]

I have a 1989 Johnson 150GT, After taking my boat out for a day I noticed really black oil coming from the two holes on the back of the engine just below the engine cover.
I removed the cover and noticed oil leaking out around the head of the bottom cylinder on the left "bank" of cylinders. Does this indicate a blown head gasket? If so what could cause it and do I need to address that issue? Also does this mean I just need to replace the gasket? Thanks for any help anyone can provide.

 

[OBJ]

Re: Blown head gasket?

If you are sure the leak is between the block and head then it definitly demands attention. Running as is could cause even greater damage if the gasket is blown. Changing the head gasket is not a large job and the only real special tool needed is a torque wrench.

Also, look very carefully at the exhaust cover gaskets. The leak maybe there and blowing onto the head.

What you may need to do is start the engine long enough to verify where the leak is before tearing into it.

 

[F_R]

Re: Blown head gasket?

It is really hard to imagine how a blown head gasket could blow oil. The oil would have to come from the combustion chamber, cross the water jacket and then to the outside. If the water jacket was open to the outside you would have a major water leak. In addition, there would be so much water getting into the cylinder that it wouldn't run, at least on that cylinder.

Look for another cause.

 

[tinny]

Re: Blown head gasket?

Thanks guys, seems you pointed me in the right direction! I did find loose bolts on the exhaust cover. re-tightend them and cleaned the area. I ran the engine and so far no oil. I have encountered another problem tho. LOL! after putting the muffs on and turning the water on and starting the engine I see water coming from between the gear case and the midsection. Sorry to be such a pain, this is my first "big" engine and has me a bit intimidated.

 

[OBJ]

Re: Blown head gasket?

Using muffs to run the engine will cause water to leak out there and is nothing to worry about. There is no gasket there and applying water to the lower unit water intakes under pressure will cause water to come out in strange places. Again....nothing to worry about.