Water in oil in a 1979 mercruiser 898

[KingFloyd]

I have noticed that the oil is milky white and extremely thin in my 898 Mercruiser I/O. I changed the oil and noticed it was much more then 5 quarts. As soon as I started it with the new oil (after hooking up the hose to the outdrive, because it's on a trailer now) the oil turned milky even worse. Prior to storing the boat in my yard, it ran perfectly well and was in the water for the entire season. But sitting out of the water since Nov 2008 must have done something because I am now having a major problem. I have pulled the intake manifold off, to take a look but before I pull the heads off, I heard that the exhaust manifold may have something to do with this. I also noticed the milky oil at the top of the dip stick tube almost bubling.
Can someone shed some light on this?

 

[Don S]

Re: Water in oil in a 1979 mercruiser 898

99% chance you have a cracked block. Probably under the intake manifold in the water jacket around the cylinders.
One of the first places that cracks when frozen with water in the block.

 

[KingFloyd]

Re: Water in oil in a 1979 mercruiser 898

Is there any sure way to check for a cracked block without removing the heads? I have the intake manifold off. I also noticed that before I took the engine apart I had pretty decent oil pressure, even though it was milky white.

 

[ziggy]

Re: Water in oil in a 1979 mercruiser 898

ya might wanna read this...

http://www.boatfix.com/merc/Bullet/01/01_13.pdf

 

[Don S]

Re: Water in oil in a 1979 mercruiser 898

Is there any sure way to check for a cracked block without removing the heads? I have the intake manifold off.

Sure, just make some block off plates and gaskets to cover the water passages on the heads where the intake mounted. Then pressurize the block, you may be able to see the crack.

 

[Howard Sterndrive]

Re: Water in oil in a 1979 mercruiser 898

Is there any sure way to check for a cracked block without removing the heads? I have the intake manifold off.

if the block is cracked, ....with the intake off, you should be staring right at a half dozen cracks in the thin casting near the lifters.... look for rust streaks in the cast iron.

 

[Bondo]

Re: Water in oil in a 1979 mercruiser 898

But sitting out of the water since Nov 2008 must have done something because I am now having a major problem.

Ayuh,... Was it Winterized,..??..??

As soon as I started it with the new oil (after hooking up the hose to the outdrive, because it's on a trailer now) the oil turned milky even worse.I heard that the exhaust manifold may have something to do with this. I also noticed the milky oil at the top of the dip stick tube almost bubling.

Ayuh,...

While the Manifolds are probably Junk Too,...

You have a Cracked Block,....

The manifolds will Not cause this with the motor Running....
Only after Shut-down,+ very Slowly at that...

 

[KingFloyd]

Re: Water in oil in a 1979 mercruiser 898

I checked the inside of the engine under the intake manifold and didn't see any cracks whatsoever. I replaced the intake manifold gasket and put back the intake. Removed the spark plugs and cranked the engine. So far it spins freely. I will try to pump water into the hose going into the engine to see if anything drips into the oil pan. Wish me luck!!!!

 

[Don S]

Re: Water in oil in a 1979 mercruiser 898

I will try to pump water into the hose going into the engine to see if anything drips into the oil pan. Wish me luck!!!!

That is not how you test for water.
Pressure test with air and listen.

 

[KingFloyd]

Re: Water in oil in a 1979 mercruiser 898

Well it looks like someone is looking out for me up there. After putting back the intake and changing the gaskets and after 3 oil changes it looks like mt oil is water free.
Thank you all for your great input. However I need to ask you one more thing. It seems now I have a different problem. It seems that the impeller is not working or maybe something else, because with the hose hooked up to the outdrive, no water makes it to the water pump. If I pumped the water dirrectly into the water pump, everything seems ok. Is there anything other then the impeller that might prevent water from reaching the water pump? Is there any shafts that might have fallen out of place in the outdrive? And if not could someone let me know the easiest way to check/change the impeller, or make sure the water is pumped up to the water pump.
Are there any links to instructions (for a fee or for free) on how to check and change this the easiest. I have a trip to Florida coming up in the beginning of March and I am staring to panick since all arrengements pivot around the boat.

 

[WizeOne]

Re: Water in oil in a 1979 mercruiser 898

I'd follow Don's advice before you declared it fixed. Water in the oil is not an intermittant thing. There has to be a reason for it.

 

[240ghb]

Re: Water in oil in a 1979 mercruiser 898

I have come into a boat that i believe was sunk on the trailer 1978 Sea Ray seday bridge with an 898. I pumped the oil out and it was milky grey about 2.5 gallons. Where to start? what is the best way to get the rest of the water out? Seafoam, remove plugs and crank?
Please help.
Thanks
GHB

 

[monico]

Re: Water in oil in a 1979 mercruiser 898

Hi guy's, I pulled intake manifold. I found a crack on the right side behind rods. The crack is 3/4" from bottom of the head. Crack is shaped like an upside down U shape 3-1/2" long. Left leg is 3/4" long and right side is 2" long. Is there a way to fix this with cold weld? Metal stitching? Or maybe Ideal 3-4-1 rod. I've been reading that welding possibly could make it worse. Is there another option other than new block? I just spent several thousand on sugery on my eye's and can't afford new engine. Please help! Thanks, Monico