ZD30 pressure leak issues.

[PathfinderZD]

Hey chaps, family member got a 1999 zd30 pathfinder, old owner blew motor and it was recond 88000km ago, they did everything except head, but head was laser checked for cracks, my dad bought it and blocked egr, tweaked as per patrol reference manual, has been running fine since. Yesterday after 10mins of driving temp gauge went up to top, then dropped, he checked engine and was very hot and radiator top hose was stiff, hot buring smell from engine, opened cap and released pressure, took to mechanic and they opened radiator cap to find water bubbling hot, when car was stopped the young mechanic poured cold water into radiator which was boiling hot and then started car and reved it and water overflowed from radiator into overflow bottle and filled up. Mechanic did crystal check for gas in water, turned up negitive, pressure test today showed leak somewhere, also took glow plugs out and one had white substance on the tip, not sure which one though, they didnt record that. Whats your thoughts guys, cracked head, cracked head gasket, should my dad clear the ecu for fault codes etc, how do we do this??. Head coming off on weekend to inspect, different mechanic this time by request. Any info and tips etc.

Cheers fellas,

Paul