I've always been told:
Black sooty smoke - fuel system: running rich (too much fuel being delivered to the combustion chamber) - exhaust smoke smells like gasoline - deposits on the exhaust tips after the tips have been allowed to cool usually black and feels like graphite when rubbed between the fingers ... slick, but not oily.
Blue/gray smoke - oil being burned in the combustion chamber. Usually caused by broken rings, worn rings or valve stems. Exhaust smoke smells like burned oil ... deposits on the exhaust tips after the tips have been allowed to cool usually gray to black and feels oily and wet when rubbed between the fingers.
White smoke - burning anti-freeze in the combustion chamber. Usually caused by a bad head gasket ... rarely by a cracked head near a water jacket proximate to the combustion chamber. Exhaust smoke smell slightly sweet with glycol anti-freeze ... deposits on the exhaust tips after the tips have been allowed to cool usually gray to white may feel wet or chaulky when rubbed between the fingers.
I have a question as I am unfamiliar with the specific mechanics of the 355 F1 ... is the heat exchanger the same as the water radiator? If so, was the vehicle running hot? What other work was done at the time that the "heat exchanger" was changed?
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