Coolant and Oil Question

[haydo]

I recently changed the coolant in my car. And some of it disappeared..

So on further inspection I found a crack at the top of my radiator. So when the cooling system was full it would drip out of the top tank until it wasn't full no more, therefore no pressure at the top of radiator pushing the coolant out anymore.

So I then had the top tank replaced on the radiator and that solved that issue.

I am now slightly paranoid and am checking it everyday.

I think I noticed a bit of murky anti freeze in the coolant reservoir earlier probably located in the middle of the coolant. So I'm assuming it's not oil as it would float above the water would it not?

The antifreeze at the top of the radiator is a perfect green, no sign of oil so I'm wondering if I'm just convincing myself that there is a problem when there is not.

So in short, if the oil and the anti freeze was mixing would it be quite obvious eg color changes and would it be at the top of the coolant reservoir rather than middle? Any other signs.

Hoping someone can clear my mind

[phoenix]

Usually you'll notice water in the oil more so than oil in the water - it'll look like chocolate milkshake. Check dipstick and under the oil cap for signs of that.

[85AW20v]

Take the reservoir out and give it good clean, refill with new coolant and then you'll know exactly what's happening.

[haydo]

The oil seems fine to me.

Coolant was replaced last week and does look a perfect green.

Strange thing did happen though earlier. It got very dirty inside of the reservoir today. Best way to describe it is a smudge. But it is at the top above where the coolant sits. Even when the car is warm it wouldn't of gotten high enough to be where the smudge is.

Anybody experienced that before?