Car overheated noticed milky coolant in radiator

Hi,

Before you can make that determination, you need to determine exactly what happened. Is there any evidence that coolant made its way into the oil? How long was it driven when it overheated? What happens now when you try starting it?

It sounds like a head gasket, but I can't be sure. What I would like you to do is take a look through this link and see if it mirrors what is happening at this point. Once you do that, report back to me and I'll try to help you determine what the most likely cause is. Keep in mind, if the coolant was never serviced, it could be extremely dirty.

https://www.2carpros.com/articles/head-gasket-blown-test

Also, please let me know how comfortable you are if I provide directions for replacement of a head gasket.

Take care and I'll watch for your reply.

Joe

Since you are seeing the drops on the cardboard, there may be nothing wrong other than a small leak. If it starts and runs normally, I would make sure the cooling system is full and pressure test it to see if you can determine where the leak is located. It may have just overheated because it was low on coolant. Here is a link that explains how to pressure test the system. You will need a pressure tester, but most parts stores will lend/rent one to you.

https://www.2carpros.com/articles/radiator-pressure-test

On the other hand, if it doesn't seem to run properly now, let me know. At that point, we need to check the head gasket. However, based on what you described, that doesn't seem to be the problem.

I will watch for your reply.

Take care,
Joe