Your mechanic did not get all the air out the first time. A simple mistake. The fact that he started talking about replacing things instead of admitting the simple mistake is troublesome.

That is an all metal radiator. If it gives trouble it can be cleaned. Don't even think of replacing it unless it gets crushed in an accident!

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.