Omc v8 water in oil

Sbushman

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Ok guys. I really need some help here. So I've got water in my oil. But I don't know how. So today I had the hose hooked up to it for 9 hours and occasionally turned the engine over buy never started it. The oil level didn't change. So is it possible the water can only get in while the engine is running? I'm lost here. Any help would be much appreciated
 

bruceb58

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How much water got in?

Which model and year OMC do you have?
 

bruceb58

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Had you been running it at all previously this year? Are you in an area that freezes?

I am guessing you were using the fitting at the drive trunion to supply water?
 

Sbushman

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Yes I am in an area that freezes. I just got this engine and installed it. While trying to get it running smoothly I noticed the water in the oil. I have really had the engine running. The best I can do is get it running for about 10 seconds then it backfires and dies. That's why I decided to leave water running through it for the day. Like I said, it had water running through it for around 9 hours. But the oil level never changed. So I cranked the engine over for about 5/10 seconds three different times throughout the day. But still no change. I'm completely lost right now.
 

bruceb58

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I would be doing a pressure test of the coolant passages. Do a search on the site and you can find out how to do it.
 

vasy

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Water can run but it is a waste of water.
If you have a crack in the cylinder wall like mine had, it would only suck in water under pressure when the water pump starts circulating the water around the block.
Of course you need your engine running for that.
Check around the block and see if any freezer plugs popped out of place or look like out of alignment or use temporary rubber plugs or look way too new compare to others.
If you can, get a scope inside the cylinders by removing the spark plugs, I could see a lot of rust in one of my cylinders that had walls cracked around it.



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You can also take out plugs one at a time and try to start or even let run if it does, and see if any start spaying water out or are just wet and rusted compare to others.

There is a slim chance that your manifolds might be leaking.... but small. Probably just a bad block.

You said that you just got this engine, was it used or "brand new" remanufactured block?
I'd stay away from used as you never know what kinda crap people want to unload.
A new reman long block is guaranteed and not that expensive and does not add many hours to the swap compare to the troubles of the bad used engine.
You can also have bad head gasket that would let water in when the engine is running.
 
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Sbushman

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Well I did a pressure test on the cooling system. It would not hold pressure. So I'm assuming that it's a cracked block. I was told it was good, but I guess you really can't trust anyone anymore.
 

bruceb58

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Well I did a pressure test on the cooling system. It would not hold pressure. So I'm assuming that it's a cracked block. I was told it was good, but I guess you really can't trust anyone anymore.
You isolated the manifolds right? I am sure you did but have to ask!
 

Sbushman

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Yes. The manifolds were out of the equation. Checked for leaks in my connections. Still lost pressure at a steady rate
 

Sbushman

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Yes. The manifolds were out of the equation. Checked all of my connections. There was still a constant drop in pressure.
 

Sbushman

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Ok guys. Here's where I'm at. I took the intake and heads off tonight. All the cyclinders were dry and clean. Couldn't see any obvious head gasket leaks. The biggest rust trails I could see were coming from the intake into the valley. But if it was the intake gasket leaking wouldn't it leak when the water is running and not only when the engine is running. I could be wrong here. Could it still be the block? Is there any way to pressure test just the block at this point? Or is it save to say that it was the intake that was the issue? Any ideas would really help.
 

bruceb58

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No pressure testing can be done at this point.

Look for cracks!
 

Sbushman

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So if I don't see any cracks or pitting should I get a new gasket set and put it back together. Or can the block still be cracked and I just can't see it
 

Sbushman

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Ok. Well maybe I'll still order a gasket set and see what happens. Maybe I'll get lucky and it was just the intake gasket. It might take a few days to get the gasket set, but I'll post what happens when I get it back together. Thanks for all the help.
 

bruceb58

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Ok. Well maybe I'll still order a gasket set and see what happens. Maybe I'll get lucky and it was just the intake gasket. It might take a few days to get the gasket set, but I'll post what happens when I get it back together. Thanks for all the help.
True. Might be worthwhile as long as your time is cheap!
 
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