Hi guys, anyone here knows how to bleed the cooling system?

I have mitsubishi lancer 1.3 everytime i start my car from cool engine there a sound like pouring water in my left dash board.

I am thingking that there a trap air in my cooling system.

 

any input is highly appreciated

 

yeah well theres two ways you can do it,you can buy a coolant refill tool so you can put a vacuum on the entire coolant system when you have the coolant drain out sucking out the air but youll need a air compressor,or you can buy a coolant funnel that connect to the radiator neck,so when you fill the coolant system up you can rev the air bubbles out of the engine when the thermostat has opened up.