got engine oil in the coolant.

[kenca]

Hi anybody,

I have 99 montana with 200k km.

I found some engine oil in the coolant. Is this serious?

What can I do for it?

thanks

[GTP Dad]

Oil in the coolant is not a good sign. Usually it is the other way around coolant in oil. It can indicate a cracked block or a bad head gasket.

If you are using Dex-cool antifreeze it may not be oil at all, it could be Dex-cool residue. If you found it in the overflow tank then I would guess that is what it is. This stuff looks like a brown oily substance. Simply clean it out and replace with new coolant. If you have 200K and you haven't drained and flushed the cooling system this may be the time to do it.

[cdru]

If you really want to know for sure, you can send in an antifreeze substance to an analytical lab to have it tested. I've used a company called Blackstone Laboratories before, although it was for looking at antifreeze in oil, but they do the opposite as well.

[gmack221]

Are you sure its engine oil? I've never heard of engine oil getting into the coolant, I have heard of it going the other way around. I have heard of transmission fluid getting into the coolant, on automatics normally the radiator has a transmission fluid line running thru the radiator to cool the trans fluid, sometimes this gets a whole in it letting the two fluids mix. If this is the case the transmission fluid will have a white tint, the coolant will also have a milky looking skim on the top.

I would make sure its not just residue from the dexcool first though.