Water in oil

Supra99

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image.jpgSo later last summer I threw a rod through the block. I purchased a new short block. GM 5.7 vortec. Finished the install. Hooked water hose up and started it. Now have milky looking oil. Considering it isn’t the block since it’s brand new. What else could be causing this?
 

Lectro88

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My vote would be Head Gasket or Intake or both,
possibility of cracked head or intake. But would not be my 1st. pick.

I don't twist wrenches every day, but some of the others on here do and will weigh in later I suspect.

Thats a clean looking head and rockers.
 
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76SeaRay

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Start with a compression check on all cylinders. Vortec heads are prone to cracks if not handled properly but, as Lectro88 points out, more likely a head or intake gasket. Did you get the head and intake bolts torqued correctly? Did you use new head bolts or the original ones?

By the way, this should have been posted in the appropriate engines forum. Maybe the Moderator can move it for you.
 

Supra99

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It’s all new gaskets. Exhaust manifold gaskets, head gaskets and intake gaskets. Fresh oil and filter. Let sit for a week or so after adding oil. Could the recent temp fluctuation from day and night cause condensation enough to cause that? If not I’m guessing new heads or riser/riser gasket?
 

Lou C

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Ok sounds like you replaced the block but used your original heads & intake, is that right? If so I’d have the heads & intake checked by a machine shop for cracks, corrosion etc.
 

Lectro88

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1 last thing.
And this is a long shot.
Did you rtv around the intake water jacket ports. (It’s been years) I remember using red rtv in addition with the gaskets at the front and back.
The smaller square ports. If it leaks there it will run to the cam/lifter valley and that of course is in the oil and drains right down
to the oil pan.

And an old trick I did with my rebuilds.
I fired them up dry of water. (Careful)
And let the gaskets heat then re-torqued or checked head and intake torque.
I’m talking 2-3 minutes idling. Tops.
It’s extra work. But it always worked for me. But I’m talking old carb or throttle body engines.
If you run too long it’s a wrapped head or other fun stuff.
Too much with mult ports with and all the bells and whistles.
This is Not something I’m telling you to try.

It’s a carful voo-do witch doctor dance.
Of sorts.
 
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Supra99

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image.jpg
I posted this in the wrong thread earlier. I just replaced my block from previously throwing a rod through the old block. I replaced with a new 5.7 gm vortec block. All new gaskets and new head bolts torqued to spec but once hooking to the water hose and starting oil became milky after a few minutes. Oil level did not change . Considering it’s a new block what else could be the issue
 

Lou C

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Also the torque specs for the Vortec intake are much less than the pre Vortec; if the gaskets on the Vortec were torqued to the same spec as the pre Vortec they would probably leak; and if they leak at the water ports the water goes right into the cam valley & oil.
Pre Vortec : 30 ft lbs
Vortec : 12 ft lbs
 

Supra99

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Also the torque specs for the Vortec intake are much less than the pre Vortec; if the gaskets on the Vortec were torqued to the same spec as the pre Vortec they would probably leak; and if they leak at the water ports the water goes right into the cam valley & oil.
Pre Vortec : 30 ft lbs
Vortec : 12 ft lbs
Ok may be a dumb question but by adding more torque to a gasket could cause it to leak? Because I’m pretty sure I may have torqued the intake to the pre vortec specs of 30 ft lbs…… I figured with less bolts holding the intake and spread further apart it would need more ft lbs than 30
 

Lou C

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Yes that might be it. Might just have to change the gaskets and torque correctly.
 

Supra99

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Yes that might be it. Might just have to change the gaskets and torque correctly.
Will try that. Also I think I used regular gasket sealer. Would that be a problem for the corners of the intake gasket or is the red RTV the only thing you should use.

Thanks again, just seems like I’ve been endlessly chasing a relaxing day on the lake with problem after problem
 

Lou C

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Well when I did mine my cyl heads sealing surfaces were perfect because they were new reman units. My intake manifold was original, there was slight pitting on the water port area that I cleaned up but still I used some Permatex Aviation gasket sealer on the gasket in those spots. The pre-Vortec does not have the locating pins that hold the gaskets in place like the Vortec so the gasket sealer helps hold it in place while you lower the intake.
Did mine 5 years ago, no leaks, no water in oil.
When you do yours double check that torque reading and use an appropriate torque wrench (meaning a low reading one, not a 0-150 lbs unit). I have 2, one goes up to 150 the other goes up to 75 ft lbs.
This is important because I know GM had problems with the original run of intake gaskets on the Vortec intakes on their vehicles. Antifreeze in the motor oil, etc. I actually prefer the old pre Vortec for this reason. Those intake gaskets NEVER leak. Not sure if its the gaskets, or the fact that they used 4 more bolts to hold down the intake.
 

Lou C

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I think this is what you need, there are marine head gaskets (hope you used those!) but I don't think the intake gaskets are marine specific, Fel Pro is one of the better brands, just be careful with the torque.
I used their marine gasket set for my pre-Vortec V6 and they sealed fine.
 

jhande

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Before installing old heads on a new block it's important to check the head for flatness. For how-to click here. Of course check real good for any cracks.
For other than race engines we have always used Fel-Pro PermaTorque head gaskets. NO sealant (RTV) added.

Check intake manifold for flatness and cracks. Have always used Fel-Pro gaskets, actually only Fel-Pro gaskets for the entire rebuilds. The only place that needs sealant is were the manifold gasket meets the front and rear rubber block to intake gaskets in the 4 corners. To see how click here.

It is important to use proper torquing sequence and specs (ft lbs.)
 

Scott Danforth

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Did you use sealant on the head bolts as most go into the water jacket?
 

alldodge

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Intake gasket leak would be first guess
Do a compression test to see if its a head
 

Chris1956

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A bad manifold-to-riser joint will allow water into the exhaust ports. If your manifolds and risers are older, you may need to inspect the mating surfaces and clean and lap them. MerCruiser had some nice silver gaskets. They worked better than the green paper ones.
 

Lou C

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If you pull the spark plugs and crank it over would see if water got in via the cyls or not. Always good to do diagnosis before dis-assembly. Merc had a service bulletin explaining how to check for the causes of water in the oil and/or cyls.
On mine it was blown head gaskets from an overheat 3 years earlier. Interesting an oil analysis showed sodium in the motor oil (raw water cooled) both before & after the overheat. So the original head gaskets were starting to leak even before the overheat.
In your case though I’d suspect the intake gaskets based on what you reported.
 
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