Bubbling rad fluid

My rad fluid in my plastic radiator overfill tank is bubbling. what could that be? engine seems to running hot.

when?

When the car is running??? if so.....looks like its time for some head gaskets. Start the car up...when its cool....take the rad. cap off and let it run...it the fluid starts to bubble after a while.....the head gaskets are gone. I think i'm right about this....sorry man.

The part that FastSC92 left out, is "when is the fluid bubbling?"

When the car is completely cooled down, and you start it, open the radiator cap. If you see bubbles shortly, while the fluid is still cool, you need to suspect the head gaskets.

On the other hand, if the fluid does nothing, and then suddenly gets very hot and boils over, you should suspect the thermostat or water pump.

Both options suck, although the head gaskets are by far the worst.

In either case, do not run the car much and don't drive it like this before you get it fixed. Excessive heat like this can and will destroy the motor.

There is quite a bit of expertise on fixing either problem on this board. Hopefully, things turn out for the best.

good luck!

Mike O.

Lets say that this is not a good sign that it is boiling in the overflow tank. I have seen this with a rad that is plugged up pretty bad from age and lack of coolant flushes. Also if your getting hot as in past the M in NORM, you rad fan may not be running causing an overheat condition which can also cause the overflow tank to bubble.

Don't always assume an overheat condition and a boiling overflow is headgaskets. Do some basic trouble shooting first

Did I get HOT?
Is my rad fan not working?
Is my rad a bazillion years old and looking pretty sad?
Do I have a thermostat that is not opening all the way?

thanks

thanks mike......someone told me that so i wasn't sure how to explain it....thanks for clearing it up for me.

¿pac dab

Check your radiator cap, and replace it with a new 16psi if necessary. When you overheat, where is the needle on the heat gauge, and how long does it stay there?

it doesnt overheat completely, it will go halfway between M and the red zone. it stays there briefly, maybe 15 seconds then starts to cool down a bit but not much. The rad fluid only bubbles when i turn the car off and i still have all the power as i did before. sometimes the check engine light will go on for a brief second when the temp guage seems to get high. besides that, i dont know what to check or how to check it. how can i tell what part it is that is causing the problem. should i check hoses, if so which ones? how do i check if the rad is goin bad or the fan? Or if the water pump is needing replaced? need some help, thanks

Re: bubbling antifreeze

I second the notion that you should NOT run your SC in its current state. I was pretty much forced to run mine in a similar condition (boiling antifreeze, visible heat rising from the hood) back in November, mainly because it was 3am and I was 20 miles from my apartment at college. Even though I felt forced to drive her, I stopped every 5 minutes to let the engine cool ...

When I got it to the parking lot, I shut her down immediately, and did not drive till I could get a diagnostic done. By running it hot all the way home, I basically Chernobyl'd multiple cylinders and pistons ... needless to say, I am currently rebuilding a new engine, and it's running me up a small fortune.

So yeah, probable thermostat failure. Possible head gasket failure. If you run it, you risk more damage. So don't. Best of luck, post results of a diagnostic examination!

Rich

Check the condition of your coolant. When did you last have it changed? If it is old, or not the correct mix of coolant:water, its boiling point may be lowered, causing boiling. Do not drive, as if it is boiling in the engine, significant problems can form out of something that may otherwise be simple. The symptom that it heats up considerably, check engine light comes on, then cools down is similar to what my Wrangler did when it lost a water pump. Because its newer the electronics are different, but it suddenly shot all the way up, dropped all the way down, and the check gauges light came on. There was no operating symptoms beyond this, excepting boiling rad fluid and the pressure cap releasing steam. I was forced to drive it 15 more miles home without a water pump, on a 4 cyl.. amazingly I had no problems. Do not do this, as it will destroy the sc engine. The radiator bypass valve could prevent it from getting as hot as a car that didn't have one, such as the Jeep. If you can not isolate the problem, have it towed to the mechanic. I would start by checking the overflow hose for clogs, other hoses for leaks, the radiator cap, and for a siezed water pump. Probably it isn't head gaskets if you have full power, but that can easily be masked in this car.