Head Gasket Or Oil Cooler?

Hi, can’t find the answer I am looking for so thought i’d post a quick question.

I have a 2.2 n/a and after my first drive since lockdown noticed the coolant level had gone down significantly. Checked the dip stick and sure enough the oil (which was changed in March) is brown and sludgy and there is maionesse in the cam cover. Radiator and header tank are new and no obvious leaks.

My question is whether an oil cooler failure could cause water to be forced into the oil or would that always fail the other way i.e. oil into the water system instead (which I do not seem to have)? Is there any way of testing the cooler or bypassing it as a test?

Not really sure how else to diagnose exactly what has failed and I don’t want to risk driving the car to a garage and causing damage so any advise gratefully received.

Fingers crossed it’s not the head gasket as way beyond my skill level.

Cheers

Cheers

Changed the spark plugs recently? Cracking the very fragile head when spark plugs are changed is another potential cause of this. On a standard Z22SE head they only need to go slightly more than finger tight.

The oil in the cooler should be around 4 bars, so I would expect when running that it pushes in the coolant loop, not the other way around

I had oil cooler failure and, as Martin says, it was evident in the water in the header tank, not in the oil itself.

Thanks for the responses.
I’ve not changed or removed the spark plugs since I’ve owned the car (3 years) so can’t be that but thanks for the warning techieboy.
As per martinroger and struts responses, all the posts I can find re the VX220 seem to relate to oil in the water system when the cooler fails not water in the oil. I have read a generic artical regarding oil coolers that said when the engine is switched off the pressure in the cooling system can force the coolant into the oil.
Has anyone had water in the oil caused by cooler failure or does this confirm my worst case scenario of head gasket failure.

Thanks

When you switch off "hot", yes you could have water to oil transfer, but not before having had oil in the coolant ... one other thing you should bear in mind is that there can be condensation in the engine, more or less varying on your setup (open breather, pCV delete...)

If left cold with an oil cooler leak, you would have some very small crosscontamination...

Head gasket failure is pretty rare on the Z22SE but I still don't think it's oil cooler from what you're describing (although I do have a replacement for sale if you want one! ), and - to be honest - if you think head gasket is a tricky job try changing the oil cooler!