Oil and coolant mixing

[Kenneth]

Wife's 2012 Forester FB25 Engine has oil in the coolant and coolant in the oil. First, thought it was head gasket but there is no sign of head gasket leak unless it is just between the oil jacket and coolant and not on the piston side. So far I have found another way it might be mixing; that is between the o rings at the PCV connector located under the ac compressor.

The coolant side has positive pressure when warmed up and while the PCV side has a pulsing negative and positive crank case pressure, could it pull coolant into the crank case if the o rings are warn out or plastic is deformed. And when engine is cold at start could it be pumping oil vapor into the coolant side? If you know of any other way the oil and coolant can mix I would be glad to know.

 

[Javromerov]

Hi I have the same problem! I did take apart the motor and find out that the head gaskets are fine. Now I need to figure where the oil is going to the antifreeze. In the beginning it was just in the antifreeze but now it went to the actual oil pan is why I did take it apart.
How did you solve your problem?

 

[Kenneth]

Hi I have the same problem! I did take apart the motor and find out that the head gaskets are fine. Now I need to figure where the oil is going to the antifreeze. In the beginning it was just in the antifreeze but now it went to the actual oil pan is why I did take it apart.
How did you solve your problem?

I replaced the head gaskets and resealed PCV connector located under the ac compressor. I haven't had the problem since.

 

[Javromerov]

Wife's 2012 Forester FB25 Engine has oil in the coolant and coolant in the oil. First, thought it was head gasket but there is no sign of head gasket leak unless it is just between the oil jacket and coolant and not on the piston side. So far I have found another way it might be mixing; that is between the o rings at the PCV connector located under the ac compressor.
View attachment 162 The coolant side has positive pressure when warmed up and while the PCV side has a pulsing negative and positive crank case pressure, could it pull coolant into the crank case if the o rings are warn out or plastic is deformed. And when engine is cold at start could it be pumping oil vapor into the coolant side? If you know of any other way the oil and coolant can mix I would be glad to know.

I replaced the head gaskets and resealed PCV connector located under the ac compressor. I haven't had the problem since.

thanks a lot I guess I be doing the same thing.