Rubehayseed, On vehicles that are not self bleeding, you will find a bleed screw usually on the upper gooseneck. Also the overflow is not the highest point in the cooling system.

On the Saturn, the overflow tank is the highest point and where you would find the bleed screw, there is a tube that goes to the bottom of the overflow tank. This self bleeds the system.

 

Thanks for the info, Keith. I'll try to remember that in case I have any problems with mine. Do you know if this applies to all of the Saturns or just one specific line, such as the S series?

 

the previous owner did NOT remove the rubber plug out of the lower radiator hole (radiators normally come with two rubber plugs for the coolant holes) and put the new hose not realizing the hole is still plugged by that rubber piece

Happy to hear you solved the mystery, but curious as to how you came about finding out. Would you mind elaborating?

 

Rubehayseed, at the risk of another ABS mistake, as far as I know all the GM cooling systems that have the type of overflow system that the Saturn has, the ones that do not have a radiator cap on the radiator, are self bleeding. I could be wrong if for example, a model didn't have the room to make this tank the highest point in the cooling system.

I also believe that all Saturn's are reverse flow. I think that when you see the thermostat in the lower radiator hose, its a reverse flow, but I'm not real sure about that. reverse flow kinda becomes necessary when ever the compression ratio is higher than 8:1 because it pulls heat out of the combustion chamber faster. Almost all engines today except maybe diesel are reverse flow as far as I know. It started in the early 90's I believe.