Reply to "Question about expansion tank cap"

Looking at my car, I'm not sure if the cooling layout change has been made or not.


The cap for the expansion tank had just a rubber seal, so it's sealed as I bought it and as it is running now.


The main tank is 100% full, and the expansion tank runs at 50% full. It all seems to work perfectly, even in traffic 150-180-150-180-etc.

I bought some rubber gasket material and plan to just put it back the way it was.

It WAS sealing, but the rubber was seriously degrading and decaying and falling apart into the cooling system.

I lined the cap with plastic to prevent any more crap from falling into the system, but the plan now is is to put a new rubber seal back on the old cap and run the car as it's been running, as it seems to be operating perfectly.

I am more used to the newer car setups that have an expansion tank with a small vent hole, that allows the coolant level to rise and fall without pressure changes to the expansion tank (unsealed) but since mine seems to be working well as a sealed setup, I'll just leave it alone for now.