Water in Oil but no Oil in water

Folks,
I’m in need of some input. I have a 2010 5.7 with 200,000 miles. I have water in my oil. What is missing from my coolant reservoir is extra in my oil side. I do not see any signs of a blown head gasket to the combustion side. No smoke no error codes no overheating no pressure in coolant hoses. My coolant is 100% clean and just went down from max level to min in about 3000 miles.

Before assuming that it is the head gasket, I’d love to rule out everything else.

Can I rule out the oil cooler? Wouldn’t the oil go into the coolant as the cooler is on the pressure side of the oil?

looking at the heads, are the outer elongated holes for the head bolts where the oil returns? Or does it return through the timing cover?

What else could be the culprit? I’d hate to pull the heads without having eliminated everything else.

Lastly, has anyone had any luck with adding a liquid head gasket to the coolant as I assume that there is no leak between combustion and oil but rather a leak between cool and and low pressure oil.

Any input is much appreciated!

 

Valley coolant leak.

 

What I use to test for combustion gasses in the radiator.

 

Thanks. I’ll do a block test tomorrow. Could you explain the valley coolant leak? Thanks!

 

I've seen people do block tests with a rubber glove over the radiator but I think that only works on boosted engines/diesels. Might be worth checking out though.

 

Leaking below the intake manifold.
https://youtu.be/PnUL0GR6mfs?si=TBBmuEBdRlAB0412

 

Ok thanks. I now understand that. However, I do not have any obvious coolant leaks on the engine exterior. Not having seen it apart, could you tell me how a failed valley cover gasket would get coolant into the oil? Thanks again for the help!

 

How often have you changed the coolant ?
Reason I ask is the Coolant becomes acidic if not changed out.
It can wear out the seal according to the Car Care Nut Toyota Guy. This pic from his video is from a Sequoia 5.7 about the same mileage and no coolant changes.
So if you have performed regular coolant changes maybe it eliminates this problem.

 

That’s interesting. It has not been changed in the last 160000 miles that I owned it. I’d hate to part with it, but will have to do something about the water in the oil. Not sure if I want to get into a head gasket nit knowing that it could have an easier fix.

 

That coolant looks like strawberry nestle quick. Not good. That oil looks rough too. There is definitely a problem here.

 

I’ll do the block test today. If the Copland does have oil in it, would you think that the oil cooler could be the problem? I’d love anything other than the head gasket.

 

A failed oil cooler sounds plausible to me for sure, though not sure how common that is as a failure point. Theoretically after shut down the oil pressure drops to nothing and the coolant pressure remains at 16psi until it cools down and the pressure drops.

 

Worth getting the equipment to do a compression and leak down test while you’re in there.

 

Just did a block test. No indication of a failed head gasket there.

I would guess a passage between coolant and low pressure oil. Could anyone guess where that could be?

I’m ruling out oil cooler as it is on the oil pressure side. Even though my coolant doesn’t look pretty, I wouldn’t say that there’s oil in it.
Any thoughts?

 

I can’t think of a single path for coolant to get in the oil besides a cracked engine block or a leak in the oil/coolant heat exchanger. A bad head gasket leak, will allow coolant into the cylinders. While running, this burns in the combustion chamber. However after shut down, the coolant system is still under pressure and will/can push coolant into cylinders. In this case, that coolant will find its way to the oil pan. However it will also blow large clouds of white , sweet smelling smoke on startup that is almost impossible to miss.

 

All that coolant mixing with the oil , has to be bad news for the bearings in the engine. Not sure how you could flush all that stuff out and not have the rod and main bearings live through it. If you
can find what and where the leak is , along with making the fix, I would drain everything and then pour diesel , about a gallon down into the oil fill and then the oil and crank and run a bit at idle
and then do it again after draining to at least help the bearing try to make a come back.
That hose under the intake could also cause the problem with the coolant loss.

 

If you are driving a lot of short trips you will get condensation under the oil cap, throw in a bad PCV and it can get a lot worse.. Not saying that's it, but maybe something to check?