I have a problem with my 1997 Accord overheating and I can't figure it out! I have put a new lower radiater hose in, all new heater hoses, a new radiater(which came with a new cap) and I have filled it up all the way to the top as the engine was running with the heat on. The hoses from the radiater to the overflow are also in good condition. I just pulled the thermostat out and it seems like opens up okay (put it in boiling water). My oil is a normal color and I'm not smoking or smelling anything "sweet coming out of the exhaust

My overflow tank is always full and I don't understand why. Also my radiater always has to be filled when the car gets hot because it isn't sucking the coolant back into the radiater. Does anyone have an idea what it could be??

 

Does the car overheat while driving, or does it overheat when you are stopped and idling?

Does the a/c work? When the engine is cold, start the engine and turn on the a/c. Do both fans on the radiator turn on?

 

It overheats when the car is idling and the fans( I connected the a/c fan to my regular fan because the A/C does not work) come on. As soon as I start moving the temp goes down. When the car is running and I look at the overflow tank I can see bubbles coming from the bottom of the resevoir and going to the top but the antifreeze doesn't go down.

Yesterday I had to pull over and let my car cool down so I could add some water to the radiater because it was overheating when I would stop at a stop sign but the overflow was still full.

Thanks for your rapid response PAhonda!

 

When the engine is cold, remove the radiator cap. Start the engine.

Let us know if there are bubbles coming out of the radiator. Wear safety goggles when doing this.

FYI: If your car starts to overheat, turn on the heat full blast with the recirculate off. This will help cool the coolant. You may be miserable inside the car, but you can prevent damage to the engine or head gasket.

 

Thanxs alot PAhonda I will try that when I get home. I bought a new thermostat (one that is supposed to stay open if it overheats) so I am going to put that in. What are you getting at if I see bubbles? Are you thinking I might have an air bubble? What is the RIGHT way of purging the system. I hear so many people talking about different ways to purge the system so I would like to do it THE RIGHT WAY! Thanks again for your help!

 

Here is a way to fill and bleed the air from the system on a honda accord. You don't really need the funnel he uses. I would highly suggest using a new thermostat from the Honda dealership. It will open up at the proper temperature.


If you have a ton of air bubbles coming out of the radiator, then your head gasket could be blown. Head gaskets can fail in many different ways, so you can't rule that out. There are some other things you can to before jumping to this conclusion.

The other possibility is a bad radiator cap. You may want to try your old radiator cap and see if you get the bubbles.

I think a good start is replacing the thermostat with one from Honda, replace the coolant, and bleed the air from the coolant. Then see what happens. This way, you are only doing routing maintenance.

 

Okay PAhonda I will get one from the dealership and I'll let you know how it turned out. Thanks again for all your help and prompt replys!!

 

I may of figured out why I was overheating. When I put the old thermostat in boiling water it DID NOT open. To me it seems odd because my heat worked really good-or doesn't that have anything to do with it?

 

Check that pickup tube inside the reservoir is connected to reservoir cap and doesn't have a hole somewhere allowing air to enter instead of coolant.

good luck

 

I think hot water from the head can circulate to the heater core even when the thermostat is closed.

As far as sucking air in when it cools down, check the radiator neck as well as the cap. The top-most rim of the radiator neck seals against the largest-diameter rubber gasket inside the cap. Scratches or gouges in the plastic radiator neck will allow air to suck in, even with a good cap. Of course, check the reservoir-hose & everything else too.