Exactly. Firstly, there is indeed xxx amount of water pressure produced via the waterpump. Ex; take a thermostat out on a cold motor, replace the housing, disconnect the upper radiator hose at the radiator and pinch it off to just a pencil size escape hole, start the car, rap the rpms, and watch the water squirt 20 feet! The water pump alone is somehow pumping coolant into the oil somewhere, or it is being pressured or sucked into the oil via piston action.
As you said, the oil pressure would come up first, (at idle), more than the water pressure, therefore oil would be going into the cooling system, (opposite of what is happening).

I am actually quite intrigued by this and looking forward to the challenge of resolving this mystery.

I will recheck all the standard mentioned checks once again later today.

Thanks Again and will update as soon as I can !!!

 

You may want to recheck your hoses. Maybe you switched two hoses and hooked up a coolant hose to the PVC system?

 

Now wouldn't that be Awesome !!! I did check that before, and that is indeed on my list of re-checks before I tear the head off again. And along those lines, I am wondering if there is something else besides a PCV/Coolant system hose mis-match that could produce this same "mix"...?

Great advice!

Thank You and Be Well

 

Is it an automatic check the transmission oil cooler and see if its damaged. Check the transmission oil to see if its milky. If so u can install an independent oil cooler and you need to flush the heater core. If tje head was cracked i think you would have seen It after lifting it so much times but check to make sure the cylinder head and bottom half isn't pitted. Due to water use instead of coolant.

 

Yes, It's an automatic.The ATF looks great and the cooler shows no damage. The head was only visually inspected for cracks, and I am unsure of the possibility that these particular heads can or tend to crack internally, (I think all heads can do that), which is why I would have it pressure tested this time around. The block deck and newly resurfaced head are also looking perfect.

My gut is still leading me to think there are hoses crossed or an external cooling/oil related part failed or clogged.

I had the IACV off to clean it out do to the fluctuating idle, which fixed that issue. It does have coolant lines going to it, but nothing oil related that I know of.

Was hopeful that an Oil Cooler failed, (a good possible mix place), but I don't see one or have found one to be a stock part for these motors.

And the mystery continues. Perhaps I somehow screwed up the gasket install, but that would be a pretty good jump, (based on the design), for coolant to access the oil ports and still not show any signs of compression loss to the cooling system or elsewhere.

I'll hit it again late this afternoon and update should I find anything.

Thank You, and Enjoy the Weekend !

 

The crankcase vent - there's one connection with the PCV valve & a hose over to the intake manifold.

But the other vent from the valvecover, connects to a metal tube that's attached to another metal tube. One tube is the air vent, the other tube is antifreeze. Make sure you don't have those crossed.

 

Wow, I sooooo wish that could have been the problem! Thankfully, they designed these lines in a way that, although the tubes are joined, it would be a small challenge to mix them up.

I attached a pic for anyone interested in this possibility.
'A' is a water line, 'B' is an air intake line, and 'C' is the PCV line.

Anyway, Bravo to your thinking, because that is exactly what my original gut feeling was telling me as well, and the first thing I looked for. (These hoses particularly because they are so frik'in close together).

Thank You !!! Any other guesses???

Enjoy!

 

It looks correctly plugged in there in the photo.Is there any water pipes or lines behind the intake back there that could be mixed.I'm just asking,throwing ideas out there,but do not know if there's any that could be connected in a way to have coolant get sucked into the engine and pumped through the system.

I'm really curious myself whats wrong,and best luck finding it.Hopefully its something simple or over looked,nothing serious.

 

I have been behind the intake with a mirror and from below a few times now, and and I cannot see anything that would cause the 'smoothie'.

It looks as tho I cannot get back to it until late tonight or early afternoon tomorrow, and will Absolutely post what I find.

Thanks for your ideas and Luck Wish.

Peace

 

Yeah, I forgot about that candycane bend on the crankcase vent water pipe. (I don't have the 1998 any more)