Yes poorly adjusted lash can cause a retarding effect to timing which increases heat lingering in top-end, or head, which can elevate coolant temperature above normal. Also a badly corroded water jacket can exacerbate "heat of combustion" retention in casting and form localized hot spots that produce boiling on jacket's surface.

Both less than 50% of antifreeze to water mix, and less than 16 psi radiator cap will lower coolant boiling point in the system as well.

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67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC