Is coolant in radiator full?
Was system bled of air?
Are the cooling fans working?
It is possible the head gasket is bad due to previous overheating as replacement of the radiator and thermostat indicates. Further testings would be required but the timing belt cover melting does not bode well.

Answered by KHLow2008 (expert)
39,832 answers provided

coolamt is full. coolant fans work. i didnt bleed the air out? how do i bleed the air out? Thanks for the fast response.

Response from andrewcoakley
8 questions asked

After everything installed, top up coolant. Run engine without radiator cap for a few minutes. Top up coolant whenever necessary. After 5 minutes, turn engine off.
Wait a few minutes and top up coolant. Start engine and top up coolant. Once coolant level stabilises, close radiator cap.

Run until operating temperature and stop engine. Wait for engine to cool down before removing radiator cap to check. Repeat above process until coolant stabilises.

The oil leak and melting timing belt cover indicates you most probably has damaged the head gasket.
You can try retorquing the cylinder head bolts to see if helps.

Answered by KHLow2008 (expert)
39,832 answers provided

Thanks for all the info. greatly apprecate it.

Response from andrewcoakley
8 questions asked

You're welcome.

Btw i forgot one thing, turn the heater on while doing the bleeding, that would get all the air out of system as well.

Answered by KHLow2008 (expert)
39,832 answers provided