Engine 1994 radiator/ coolant issues

[Mike0331]

I have been losing coolant and do no think I have a leak. My car is a 3.8 engine. Just recently I have been seeing a lot of gunk under my radiator cap and at the top of the radiator. I have used 50,50 coolant mix I mixed myself, but used tap water which I hear is not good. I have changed my oil recently and it did not look like "chocolate milk" and I don't think it had coolant in it. Here are pics. Should I try to flush my system and replace thermostat while doing so so it get it all done at once? What is the best method of flushing? Thank you

 

[General karthief]

A flush and new cap and thermostat could be what you need but first I would get a test kit from an auto parts store to check for combustion residues in you coolant.
i would guess a cracked head or bad head gasket problem.

 

[Mike0331]

A flush and new cap and thermostat could be what you need but first I would get a test kit from an auto parts store to check for combustion residues in you coolant.
i would guess a cracked head or bad head gasket problem.

Okay, I will be trying that first. I have had suspicions of a bad head gasket for a long time( like over a year). Is it possible for a head gasket to not blow in that amount of time for a daily driver?

 

[General karthief]

If you mean blow like boom with white smoke billowing everywhere, yes, would not be unusual,

 

[jozsefsz]

Unfortunately with the 3.8 the head gasket is always suspect. I've usually known them to blow coolant into the combustion chamber though (and fill the oil sump pretty quckly with coolant), and not to draw oil into the coolant which is what it looks like you have going on.

I have seen the 3.8 suck oil into the coolant via a bad lower intake manifold gasket. Might be worth a shot. You could also do a leakdown test to see if you get bubbling through the radiator.