water in oil after intake gasket?...

[9fingers]

I just traded for a boat and there was well over a gallon of water in the crank case.. The guy I got it from said he has had everything pressure tested (I don't know how much I believe him...) and block and head are sealed with no water leaks. He said the water is from when he changed the exhaust/intake gasket. Is that possible on a mercruiser 165hp 250cid L6? I've seen it a lot in v8 engines but never heard of it in an inline.. He had never used the drain plug and says that's why water is still there. (he used a pump thru the dipstick..) I haven't done anything but pull the plug and drain it out.


-1974 aristocraft nineteen
-Mercruiser 165hp

 

[alldodge]

Over a gallon, sorry for you loss but you have been had. My first guess is the block is cracked and the motor is trashed. Agree you can pump the oil out the dip stick but that was not the case for the inline 6.

 

[Bondo]

He said the water is from when he changed the exhaust/intake gasket.

Ayuh,.... Welcome Aboard,..... You were lied too,....

I'm guessin' it's a cracked block,.....

 

[9fingers]

A cracked block or head was my first guess too. Pulled the top hose and filled the engine with water with the plug out of the pan and no leak yet.. But it's also not under any pressure. So at least if it's cracked it's not that big?.. He also said the head was pulled.. I've seen a lot of water get in from that and it would make sense that he couldn't get all the water out from the dipstick. We shall see! Today I'm filling the oil and give her a test run.

 

[Newbie@boats]

Hope you didn't trade him anything good

 

[Maclin]

If water is getting into the crankcase from the cooling water jackets then it is "that bad", will need block replacement more than likely.

 

[harleyman1975]

If there was a gallon of water then most likely time to pull it... if it sat more than a week...rusty crank journals.

 

[9fingers]

Blown head gasket between 2&3!

 

[9fingers]

Hope you didn't trade him anything good

not really.. 90&91 Kawasaki TS.

 

[Maclin]

Just sayin' head gasket problems can only get water into the crankcase via the cylinder past the piston rings, and in all likelihood would not account for a gallon of water in the crankcase. Keep looking.

 

[9fingers]

Just sayin' head gasket problems can only get water into the crankcase via the cylinder past the piston rings, and in all likelihood would not account for a gallon of water in the crankcase. Keep looking.

True. But I've Worked on cars and trucks with the same issue and the same if not more coolent in the crankcase, did a gasket and a few oil changes and good to go. Hopefully that's it. But in not oh well I suppose. Any recommendations for a good parts outlet?

 

[Newbie@boats]

Just sayin' head gasket problems can only get water into the crankcase via the cylinder past the piston rings, and in all likelihood would not account for a gallon of water in the crankcase. Keep looking.

Are you sure?


I will buy many parts from iboats or I usually go into my Sierra parts catalog and get parts from a local parts warehouse. You can always use eBay or the local marina as well

 

[Maclin]

Sorry, was thinking Manifold/Riser gasket leaking when I responded with that. Head gasket breach pressurizes the coolant passages and in a closed system will cause an overflow. In open system may see steam in exhaust. With leaking exhaust cooling passages or riser joint gaskets that can only get into cylinders, and then has to get past the rings.

A gallon of water in the crankcase needs a root cause finding, that was my main point. If the head gasket breach is only between cylinders then I would have to keep looking.

 

[9fingers]

I'm willing to bet the guy who had it last was a bit less "mechanically inclined" than he thought.. Haha I say that because he said he had it at the lake all week and never even got water from the bilge.. The hose for the bilge pump wasn't hooked up so... Of course no water from the bilge! Haha I think he just botched the head gasket. There's RTV all over the intake and valve cover caskets Also. I've never used RTV on an intake gasket. Except corners of V engines. I'll tear into her soon and see what I have.

 

[jimmbo]

You keep hoping its the cylinder head gasket, have you done a compression test?

 

[9fingers]

You keep hoping its the cylinder head gasket, have you done a compression test?

I have. No comp in both. If you crank by hand with a hose style automotive stethoscope you can hear air go between the cylinders. the gasket is blown.
got the manifold off on lunch today and it's cracked between the water jacket and the exhaust passage. Anyone have a spare manifold? Haha