Hi thanks for your help. Today i had some time so i checked that 680p capacitor and it looks fine. Im not sure if 630pf instead 680pf can be problematic? I also had 3 another 34063 uc so i swapped them, unfortunately i still have no HV after swap.
Today i had some free time and i exchanged for new ones q1 and q2 transistors and now clock is working fine. It is weird because if i check disassembled transistors with multimeter they both looking fine.
I had insufficient high voltage and a hot transistor too. Turned out to be a bone-headed assembly error; the circuit will not operate properly without the bulk output capacitor to stabilize the voltage.