Water in Oil

N

newDIYer

Seaman
Joined
Nov 25, 2002
Messages
61
1972 Mercruiser 140. Just went out to change oil and when I removed the oil pan drain bolt about a pint of water came out before the oil. I ran it all summer and never noticed water in the oil and it never ran hot. Before the first freeze I drained the block via the petcock (left petcock open). Removed the drain plug from the manifold and drain plug from the exhaust elbow. <br /><br />What could be the source of the water?<br /> 1) Not winterized correctly (as mentioned above)?<br /> 2) Blown head gasket? (Boat sat at least 5 years before I fixed it up and ran it the past 2 years) NOTE: I do have a very small trickle of oil on the port side of the engine originating from the head gasket area (only when running).<br /> 3) Cracked block?<br /> 4) Bad exhaust manifold?<br /> 5) OTHER?<br /><br />Where should I begin?<br /><br />Thanks for any help
 
C

crazy charlie

Vice Admiral
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Re: Water in Oil

There are a lot of possibilities.Lets start at the beginning.Did you flush your motor with fresh water prior to lay up???Charlie
 
N

newDIYer

Seaman
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Nov 25, 2002
Messages
61
Re: Water in Oil

No. I boat in fresh water lakes. I did not hook it up to a hose before winterizing.
 
C

crazy charlie

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Re: Water in Oil

Well that eliminates the possibility of water from flushing with too much pressure or leaving the water on while the motor was off.How do the plugs look,any rust???How did the rest of the oil look,creamy tan in color or were the oil and water seperated? Charlie
 
Walt T

Walt T

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Re: Water in Oil

Manifold or possibly rain water. Change the oil and run it a bit see what happens.
 
N

newDIYer

Seaman
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Nov 25, 2002
Messages
61
Re: Water in Oil

I have not had a chance to pull the plugs. I will do that after Christmas. I think while I am doing it I will check compression. Maybe Santa will bring be a compression check tool.<br /><br />After that I will try out your suggestion and start her up and see if any water gets into the oil. <br /><br />When I drained the oil, water came out first and then the oil(black not creamy). I looked into the oil fill hole on the valve/tappet cover and did not see any cream. Engine had not been ran since first of October. <br /><br />I have been suspecting a detoriating head gasket (hence the oil seapage). Would this cause this problem?<br /><br />Thanks for all your help! I will post back my results after Christmas.<br /><br />Thanks again and a :) MERRY CHRISMAS :) to ALL.
 
C

crazy charlie

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Re: Water in Oil

yes the head gasket could cause the water to get in the oil.Has the motor ever over heated???The gasket on a marine engine is usually made of stainless so it is less likely to degrade unless it has overheated or something similar .I would go about your business and do what you have stated,but you may get lucky.Change the oil and let it run for as long as you can.Take a look at the underside of the oil filler cap.If the motor was running with water in the oil there would usually be some cream on the cap.If there is not any ,you may get lucky.Charlie
 
N

newDIYer

Seaman
Joined
Nov 25, 2002
Messages
61
Re: Water in Oil

It has never overheated with me. Now the person that had it before me????<br /><br />Just pulled the plugs. Noticed slight red build up on bottom of plug's outer diameter on #1 and 4. Not very much red, just a little. Cathod and anode look clean on all four. <br /><br />Compression test result (remember this is the first time I have attempted this so hopefully I did it right). I did it with all plugs removed and my crank assist charger connected. I did it twice to see if I got similiar results.<br /><br />Test #1<br />#1 110<br />#2 100<br />#3 120<br />#4 60<br /><br />Test #2<br />#1 105<br />#2 85<br />#3 115<br />#4 80<br /><br />Any thoughts? I will start it up tomorrow as I have promised to help my daughter this afternoon.<br /><br />Thanks again!
 
C

crazy charlie

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Re: Water in Oil

Attach the water to the drive and let it run to normal operating temp.Check the oil and do comp test again.I think you may get more accurate readings when warm.Charlie
 
B

Bhamil

Seaman
Joined
Dec 17, 2003
Messages
71
Re: Water in Oil

That's a 3.0L GM engine, 140 (181CID), right? Compression testing will give you a lot of valuable info but, they can be misleading, too. The readings should be averaged together and the low ones (25% less than average) are suspect. With a 4 cylinder engine take the average of the two highs and the average of the two lows and see what the difference is; in this case it's 25% and that's too much difference. I would suspect a blown head gasket but don't take anyone's word for that. It's an easy head to pull so do that if you feel comfortable with doing it. Clymer sells a good book on that series engine, so does SELOC; water in the oil can come from very few places and a blown head gasket is the chief culprit, especially on this engine. If you want to walk through the process I'll send you an e-mail with complete instructions, but, please don't think I'm acting like a know-it-all, I'm not. I'm just trying to help.
 
Walt T

Walt T

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Re: Water in Oil

That's an old engine, the compression readings are pretty much normal from all the ones I've seen. Simple things first. Change the oil, take it for a spin, see what happens.
 
C

crazy charlie

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Re: Water in Oil

The fact that there was no cream or residue would lead me to believe that the engine was not run with the water in it,so thats a good thing.As suggested start it up with fresh oil and see what you have.Charlie
 
R

rattana

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Jun 12, 2003
Messages
413
Re: Water in Oil

I agree with Walt and Charlie. I would change the oil and run it and see what you have. The compression may come up a bit after running it.
 
N

newDIYer

Seaman
Joined
Nov 25, 2002
Messages
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Re: Water in Oil

Ok, I ran the engine, with hose attached) until operating temperature (about 15 minutes) and did the compression test twice. Here are the results.<br /><br />Test 1<br />#1 130<br />#2 140<br />#3 135<br />#4 120<br />*about 16% difference from high to low<br /><br />Test 2<br />#1 125<br />#2 145<br />#3 135<br />#4 120<br />*about 21% difference from high to low<br /><br />Replaced plugs and ran engine for another 30 minutes. Drained the oil and it was slighly creamy.<br /><br />Does the about compression values illimnate a blown head gasket?<br /><br />If so, what are the remaining possiblities?<br />1) Cracked Block?<br />2) Exhaust Manifold? How to test?<br />3) Other?<br /><br />Any other ideas? <br /><br />As always, THANKS for any advice.
 
C

crazy charlie

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May 22, 2003
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Re: Water in Oil

In my opinion your compression is fine.What does the oil look like now?????Is the motor running smoothe????Charlie
 
N

newDIYer

Seaman
Joined
Nov 25, 2002
Messages
61
Re: Water in Oil

Engine runs smooth, every now and then a miss. Oil is a creamy brown.
 
B

Bhamil

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Dec 17, 2003
Messages
71
Re: Water in Oil

Yep, manifold. Compression is pretty good, well within tolerance. The path of water to crankcase is the issue now, and the manifold is suspect. That's my opinion. You probably already have, but, here's what I would do; Change the oil and filter, making sure all the fluid is removed from the crankcase before adding any more. Run the engine to operating temperature for a while, say 30 minutes, then shut it down. Wait until engine is completely cool, then drain the oil into a relatively clean container and see what it looks like. If you have water in it, it must be new, and I believe it will be from a bad manifold seal. Have the manifold looked at by a machine shop and follow their suggestions. That's just me, I could be wrong.
 
N

newDIYer

Seaman
Joined
Nov 25, 2002
Messages
61
Re: Water in Oil

Thanks! I will remove the manifold and haved it checked out. If it checks bad I will replace it.<br /><br />While I am doing it I think I will replace the riser elbow also.<br /><br />Thanks again! I will post my results. May be a few days before I can procure the parts.
 
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