Water in Engine Oil 5.0 Liter MPI 2002

[joedm2000]

I change my engine oil today in preparation for winter storage and noticed the oil was milky so there is water in the oil. I don't believe there is a lot of water since I check my oil regularly though-out the season and did not notice the oil level rising.

I replaced the intake manifold gaskets this past spring and the head gaskets 2 years ago.

I need some advice in determining the location of the water leak. How can I determine if the water leak is from the manifold or the head gasket or maybe I'm missing some other location.

Thank you in advance!

 

[QBhoy]

What was the reason for replacing the gaskets previously? Suspect your answer lies around there. An unusual event to have to do this on these, without having some sort of serious event. Like an overheating perhaps. Can often have further issues if so, should the heads or their mating face have been compromised too.

 

[muc]

Might want to read the service bulletin in the first post.

https://forums.iboats.com/threads/water-in-your-oil.361825/

 

[joedm2000]

What was the reason for replacing the gaskets previously? Suspect your answer lies around there. An unusual event to have to do this on these, without having some sort of serious event. Like an overheating perhaps. Can often have further issues if so, should the heads or their mating face have been compromised too.

I replaced the intake gaskets because a small oil leak in the rear of the intake. I replaced the head gaskets because I thought the engine was Hydo locking (misdiagnosed). The Hydo locking turned out to be my stern drive locking-up at high rpms and sucking water thru the exhaust manifold, because the motor would rotate in reverse when the drive would lock-up. I replaced the Merc drive with a SEI drive which fix the problem 2 years ago. In retrospect, I really did not have to replace the head gaskets.

 

[QBhoy]

My goodness. That’s an incredible thing for an engine to lock up at high rpm, then rotate in reverse too…as a result of the drive locking up…did you verify and witness this or did someone tell you this ? Almost unimaginable

 

[joedm2000]

My goodness. That’s an incredible thing for an engine to lock up at high rpm, then rotate in reverse too…as a result of the drive locking up…did you verify and witness this or did someone tell you this ? Almost unimaginable

It was a summer of boating hell. The drive locking up was random and very frustrating. It would lock at high rpms and then move freely afterwards. Before I knew it was the drive, I would pull the plugs and water was in the cylinders. I would turn the motor over without the plugs and water would shoot out of the cylinders. The very last time the drive locked up the motor would not turn over after I removed the plugs, so I thought I bent a rod or something catastrophic. I started to tear down the motor hoping I would find something but did not after removing the heads. I tried turning the motor over again and it was still locked. I then removed the stern drive, and everything moved freely again. At that point, I replaced the stern drive and reassembled the engine, and it has been good since and have not had water in the cylinders. I know...A long story.

 

[QBhoy]

It was a summer of boating hell. The drive locking up was random and very frustrating. It would lock at high rpms and then move freely afterwards. Before I knew it was the drive, I would pull the plugs and water was in the cylinders. I would turn the motor over without the plugs and water would shoot out of the cylinders. The very last time the drive locked up the motor would not turn over after I removed the plugs, so I thought I bent a rod or something catastrophic. I started to tear down the motor hoping I would find something but did not after removing the heads. I tried turning the motor over again and it was still locked. I then removed the stern drive, and everything moved freely again. At that point, I replaced the stern drive and reassembled the engine, and it has been good since and have not had water in the cylinders. I know...A long story.

Sounds like you’ve had a hell of a time of it. Likely one of the guys more knowledgeable than I, might have a better notion on things.

 

[joedm2000]

Might want to read the service bulletin in the first post.

https://forums.iboats.com/threads/water-in-your-oil.361825/

Thanks for the reply!! I have a feeling it is the intake manifold gasket. Is there a way I can know for sure without pulling the intake off?

 

[stresspoint]

the problem you have is without tearing the top end of the motor down you are not going to find the smoking gun .
you need to get that milky oil dispersed before going any further .
i found going to a local garage and grabbing a few jugs of used oil was the best option for flushing water logged oil out of a motor without the expense and waste of using new oil.

when you do the tare down when you are unsure of where the water is getting in gasket reading is important , don't just rip stuff apart until you find a definite where you have a leak .

looks like a top end tare down is in your future . keep posted with results.

 

[alldodge]

Thanks for the reply!! I have a feeling it is the intake manifold gasket. Is there a way I can know for sure without pulling the intake off?

Don't know of any test. Very high chance its the intake. Its either the intake or head gasket, so the intake has to come off first

That is, if the motor has not been dieseling or something else is going on

 

[joedm2000]

Don't know of any test. Very high chance its the intake. Its either the intake or head gasket, so the intake has to come off first

That is, if the motor has not been dieseling or something else is going on

Thanks...Motor runs great...No dieseling...It does appear that Vortec motors do have issues with water leaking into the motor from the intake. I did replace the intake gasket in the spring because of a small oil leak and noticed a small amount of pitting around the water ports. I did not use any silicon/rtv around the water ports when reassembling. In retrospect I should have.

 

[joedm2000]

the problem you have is without tearing the top end of the motor down you are not going to find the smoking gun .
you need to get that milky oil dispersed before going any further .
i found going to a local garage and grabbing a few jugs of used oil was the best option for flushing water logged oil out of a motor without the expense and waste of using new oil.

when you do the tare down when you are unsure of where the water is getting in gasket reading is important , don't just rip stuff apart until you find a definite where you have a leak .

looks like a top end tare down is in your future . keep posted with results.

Thanks for your reply. I need to clone myself to get all of my fun projects completed.

 

[Scott Danforth]

Drain the water jacket and do a pressure test

Could be exhaust manifolds. Are you in salt water?

 

[alldodge]

Thanks...Motor runs great...No dieseling...It does appear that Vortec motors do have issues with water leaking into the motor from the intake. I did replace the intake gasket in the spring because of a small oil leak and noticed a small amount of pitting around the water ports. I did not use any silicon/rtv around the water ports when reassembling. In retrospect I should have.

RTV is used only in the bottom corners of the intake gasket and bead along valley, it should not go around the intake port

 

[Scott06]

Thanks for the reply!! I have a feeling it is the intake manifold gasket. Is there a way I can know for sure without pulling the intake off?

You could pressure test the cooling system to verify the leak before tearing into it. Other thing is to look into exhaust system trickling water into exhaust . Would think you would see evidence of this on spark plugs

 

[joedm2000]

Drain the water jacket and do a pressure test

Could be exhaust manifolds. Are you in salt water?

Thanks..No salt water. The exhaust manifolds looked good a couple of years ago. I did a pressure test a couple of years ago as well. That is a good suggestion. What pressure should I put thru the system? I forget what I did in the past. If I remember correctly, I sealed off the exhaust at the riser for pressure test.

 

[Scott Danforth]

Thanks..No salt water. The exhaust manifolds looked good a couple of years ago. I did a pressure test a couple of years ago as well. That is a good suggestion. What pressure should I put thru the system? I forget what I did in the past. If I remember correctly, I sealed off the exhaust at the riser for pressure test.

The block&heads should hold 15-20 psi forever

You click off the lines to the manifold and elbows