Chicken and Egg Heads - what comes first?

[Holly2007]

Does a head crack because the radiator is empty or does the cracked head drain the radiator? Interested to boost my limited knowledge on engines.....

Context - history since getting car (3TD 94)

- car overheated - empty radiator
- mechanic reconditioned radiator - said core had gone.
- back on road including a 5 hour tailback ont the M27 as someone nicely decided to die on the motorway (auspicious)
- car overheated - empty radiator.
- confirmed cracked head
- currently replacing head (courtesy of stevo (thanks))

so my basic question is - is it likley that once i have replaced the head that I still have a leak in the system or could it have been a cracked head. could I have driven on a blown gasket head without knowing until the radiator ran out and caused my problems.

thanks y'all

[MattF]

Could be either way. Pressurising the coolant system with a head crack could have ditched a lot of the coolant through the expansion bottle or anywhere else where there's an escape route. Running out of coolant would eventually crack the head. You need to service the cooling system fully whilst you're replacing the head. You could have a leak, the coolant could have been forced out. No real way of telling. You'll have to replace rad cap, thermostat and any possibly dodgy hoses. Check all coolant system hoses are inplace and on snugly. Then keep an eagle eye on the coolant for the first few weeks of driving.

[BUSHWHACKER]

Also, give all the rubber hoses a squeeze to make sure they haven't gone brittle inside causing blockages.