What causes the radiator fluid/antifreeze to overflow out of the reservoir after running the car? Engine was not overheating - OEM temp gauge shows just slightly below halfway mark. Supplemental cooling fan did kick on and was running when I got out and I noticed fluid leaking steadily. Fluid was that spendy Pentosin stuff. Was steaming/flowing out from the cap on the new aluminum coolant reservoir tank. About to be done with this car. Love it and am now hating it. Suggestions?

 

Too much coolant in system?

 

Did you put a new cap on when you got the tank or reuse the old one? I'd check the cap and make sure it's not in poor condition.

 

Reused it. Because I'm either cheap or broke after all the $$ i've spent on the Tardis in the last six months.

 

Check and make sure the seal on the cap isn't bad. It's also good, as mentioned above, to make sure there isn't too much coolant in the system.

https://www.northamericanmotoring.co...erflowing.html
https://www.northamericanmotoring.co...-overflaw.html

 

Have patience. On the aluminum recovery tanks, (Forge, Canton, etc.) you want coolant only about 1 inch above the bottom when cold. Use a piece of wooden dowel to check. Then go buy yourself a higher rated pressure cap...22-24 Pounds.

 

When that was happening to me it was a bad thermostat. Temperature was normal both on the gauge and via obd, but it was still bubbling over. I have the Forge tank too.

 

Your not alone. Just bought a new aluminum tank this weekend. I have the same symptom as you now. I have a new OEM cap and my old one. Looks like my new cap isn't much better than my old OEM cap. Still, the fluid is doing the same thing as yours. Also new water pump, housing, and thermostat.

 

Thanks Trackrat. I will check that coolant level as you suggest. I think it may have just be too full and released the excess. I do hate that I cannot see the level in the container without opening the cap but such is life. Thanks again.