Coolant suddenly sucked into the oil

Rockovert

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I recently replaced every gasket possible in my 7.3 idi and it was running perfect for about 2k miles. I started it up one day and all of a sudden, smoke went out my tailpipe and all of my coolant got sucked into the oil. Im hoping this isnt cavitation. I don’t know why it would be a head gasket considering i have studs installed. I dont see any external leaks either. Any ideas on what it could be, and easy tests for it?
 

homelessduck

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I wouldn't think coolant would empty that fast from cavitation. Did you reseal the oil cooler?
 

Dane Rickford

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If your cooler failed, I would expect to see oil in the coolant, not coolant in the oil. This is because there’s around 50 psi for the oil, and only around 8-12 psi for the coolant in the cooler, therefore the oil would go into the coolant because it’s at a much higher pressure. At least that’s what happened to me
 

homelessduck

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If your cooler failed, I would expect to see oil in the coolant, not coolant in the oil. This is because there’s around 50 psi for the oil, and only around 8-12 psi for the coolant in the cooler, therefore the oil would go into the coolant because it’s at a much higher pressure. At least that’s what happened to me

It is possible for the coolant to get in to the oil from a failed oil cooler. I would start with a compression test . Is there coolant in any cylinders? How did the water pump backing plate look when you resealed it?
 

homelessduck

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Unfortunately, with smoke suddenly coming out of your exhaust, I think that the oil cooler isn't very likely.

Oil cooler won’t do that, head gasket, head issue or cavitation.

I missed the smoke part and for it to be the oil cooler it would usually only happen when the engine is off ( 0 oil pressure but cooling system is still pressurized) , so scratch that. Luckily it didn't hydrolock and cause more damage.
Wouldn't cavitation take longer to empty the cooling system since it's only pinholes? I would think it would have to be a pretty large leak to empty that fast. A leak down test of each cylinder at tdc and again at the bottom of the stroke would help determine if it's cavitation.
 
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Black dawg

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Does it still run? I have seen a couple drop valves and knock out the cylinder wall. THat will fill the crankcase with coolant real fast......wont suck it in there though?
 

Rockovert

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Does it still run? I have seen a couple drop valves and knock out the cylinder wall. THat will fill the crankcase with coolant real fast......wont suck it in there though?
Yeah it still runs, at this point im just gonna pull the motor again and take it all apart to see
 

Rockovert

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Update: had the motor apart and took everything to a machine shop. Rip my project, both heads are cracked and are no good. I dont know where to go from here.
 
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