Update ko lang additional findings and actions ko. Also have few questions.

- Placed the vehicle on an inclined area and bled the radiator for possible air.
- radiator fan speed is ok pero madali lang syang ikutin pag naka stop engine. Is this loose or normal. How do I tighten it?
- After driving, nag lagay ako ng newspaper sa ilalim ng engine to findout kung meron leak ang water pump and etc. Left it to idle for a few minutes - then parked it overnight. End result is negative leaks.
- Next day at idle, I've noticed some bubbles on the radiator top opening after topping up with water. After placing back the radiator cap, the upper radiator hose becomes hard after few minutes of idle. After being driven on a highway for about 15mins or 10-15kms, I've noticed bubble noise coming from the overflow container. When I opened it, it was full of water/coolant and bubbles were visible as if it was boiling. I think there is air pressure coming from the Radiator? Slowly openned the radiator cap, then I've noticed bawas na yung tubig ng close to 1L. Also noticed intermittent light gray smoke during idle on traffics and light to medium Black Smoke on 3000rpm while driving.

Signs of BHG? Top Overhaul?