Need help: Brown coolant overflowing from resevoir

[NA97GT]

Im having a problem with overflowing milky-brown coolant sludge from my overflow tank. Once the car warms up the sludge keeps pouring out of the opening with the cap off. Revving the engine makes the coolant level decrease and not overflow, but idling will continue to overflow. No smoke from exhaust, and no overheating is occurring.

My oil level is decreasing but the dipstick shows no signs of coolant in the oil. I've replaced my oil cooler assembly about 4 years ago, and the car is at 160k. Is this likely a head gasket or other internal fault? what should I do next?

 

[DHG1078]

Sounds like a bad head gasket to me. Its a repair that needs to be done sooner rather than later. But until the repair is done you MUST keep the oil topped off. Check it every day and carry a bottle of oil with you at all times. I would flush the coolant system constantly as well. You do not want to let the car overheat because it has bad/ insufficient coolant. If you have something else to drive, or can carpool in the mean time, I would recommend not driving your mustang.

 

[NA97GT]

Sounds like a bad head gasket to me. Its a repair that needs to be done sooner rather than later. But until the repair is done you MUST keep the oil topped off. Check it every day and carry a bottle of oil with you at all times. I would flush the coolant system constantly as well. You do not want to let the car overheat because it has bad/ insufficient coolant. If you have something else to drive, or can carpool in the mean time, I would recommend not driving your mustang.

Thanks for the reply. The mustang is parked and wont be driven until I repair it. I got a engine leak tester from autozone that tests the coolant for exhaust but, I cant get it to work due to the coolant pouring from the overflow cap. Do you think that a compression test will give me a good enough indication that it is for sure the head gasket?

 

[DHG1078]

A compression test wont necessarily confirm a bad head gasket, but rather eliminates other possibilities. Honestly the most common way to get oil in your coolant from what I have seen is through a blown head gasket. Its a common problem. I have heard of bad head gaskets causing coolant overflow as well. Might be a good time to think about upgrading heads/cams while your at it if that was something you were interested in doing since your taking it all off anyways.