Sounds like an air bubble in the system. Refill the radiator and while the car is running, knead the coolant hoses. Leave your radiator cap off while you do this. You should see some bubbles (big ones) come out. Your coolant level will drop down while you are doing this, so make sure you keep it topped up.
Absolutely do not swap out to a plastic radiator. I've never heard of any manufacturer using a plastic radiator, so I hope you're not getting mixed up somewhere.
You must have a leak somewhere in the system. Possibly just a hose with a pinhole. That won't make any smoke, it will just slowly pee the system dry. Start up the car and then check over everything, you might find where the hole is. It probably only happens when the system is under pressure (ie running).
|