In the mean time I have verified that the problem is with

emulatedMachine=pc-i440fx-rhel7.3.0

Summarizing:

default boot ofengine VM after update to 4.1.3 is with cpuType=Broadwell and emulatedMachine=pc-i440fx-rhel7.3.0 and the engine vm hangs at "Booting from Hard Disk " screen

When starting with cpuType=qemu64 and emulatedMachine=pc-i440fx-rhel7.2.0 the engine comes up normally
When starting with cpuType=Broadwell and emulatedMachine=pc-i440fx-rhel7.2.0 the engine comes up normally
When starting with cpuType=qemu64 and emulatedMachine=pc-i440fx-rhel7.3.0 the engine vm hangs at "Booting from Hard Disk " screen

Gianluca