Thread: Coolant overflow empty after 2 days?

I drive daily about 40 miles (20 one way to work). Don't have an aftermarket temp gauge, but can say it rarely goes up to even a 1/4 of the gauge since the cold weather is here, never passes half.

I filled the overflow reservoir up to the max 2 days ago, and I pop the hood to see it, and it's completly empty. What I do know is the reservoir has no hole in it, replaced the hose going to the radiator from the reservoir.

Not sure where to start looking. No leaks or pooling when I do park it though.

any white smoke out of the tailpipe (head gasket)?

No white smoke also had the radiator fill cap replaced. Visually 2 shops couldn't see any leaks.

Have you changed the coolant lately? It could have been slightly low - you might want to refill it and keep an eye on it.

If your radiator has a hairline crack, you might not see any coolant leaking since it will seep when it is pressurized. If that is it, I would drive the car and leave it running while checking everything.

Josh

First thing to do is do a good cooling system bleed. Get the car up on jack stands so the rad cap becomes the highest point by a good bit. Then start you car with the cap off and start squeezing hoses. You will probably see some air bubbles come up thru the rad opening. Let it idle for a while and then start adding coolant and fill your bottle. Make sure you let it idle until it gets warm, and squeeze the hoses some more. Be sure to put the heater on full warm so the coolant goes thru the heater core too. I have had to do that several times, as it seems like my se-r's heater core traps or accumulates air somehow. I'd give that a try and then see how it does.

Check your heater hoses for leaks, no matter how small. Old hose can get a hairline crack and go undiagnosed for a long time before bad things can happen. I almost lost my DE recently even though I had replaced both heater hoses and fixed one leak. The other leak was in the hoses going to the throttle body that were 17 years old and were hidden under the highport intake manifold. I could smell coolant even after I fixed both heater hoses. If you can, see if you can smell coolant after you shut off the car. Check under the hood and under the dash inside. At least it's a start. Visually I couldn't see any leaks but I smelled coolant after shutoff and my reservoir lost coolant a lot.

There are a couple of coolant hoses on the under side of the intake manifold - check those
Also, check the rubber parts of the water tube - they almost never get replaced

NAPA sells a block tester that will turn color if there is a leaking head gasket. That's how I found out I had to replace the motor in the wife's Tahoe. My brother turned me onto this little tool, cause I was not convinced the gasket was faulty.

reproman

You realize that the overflow changes levels right? It will pull coolant in as it warms up. If it was low it will not return to the overflow. Make sure the system is bled and full and then add it to the overflow. Watch it over the next few days....

Blown head gaskets will typically airlock the system due to flash boiling and cause the car to overheat.

Exactly what I'm saying... bleed the system and make sure that the rad and motor and all hoses are completely full, then fill the overflow. If you have air pockets in your hoses, they'll expand and contract and mess with the whole thing.