So i have filled my cooling system and bled it properly multiple times. I know you fill it from the filler neck until the ast fills up then close the ast cap and never open again. My question is where does the coolant go once you open the ast cap again? I know your not supposed to but Its not coming out the filler neck. The overflow bottle is at the same level. Where is the coolant draining to? Why cant you open the ast? There is hose that goes to the ast to the filler neck. How can i make sure there is no air in it after i top up the coolant after a few drive cycles?

 

It shouldn't go out the filler neck when cold. The AST has a vent to relieve pressure on the system. If your over flow isnt moving you should be just fine. Just keep an eye on the overflow. Add as needed (which shouldn't be much or often)

 

Yeah i only fill from the filler neck and put the ast cap on when its filled from the filler neck and never open it again. But im wondering after you do open the ast and it sinks down after bleeding where is the coolant going.

 

Disconnect your throttle body coolant line. This will allow air to escape the system when you fill the coolant. Fill the AST. Cap it and fill the filer neck. Re connect the Throttle body coolant line.

You may have to do this twice. This should remove all the air from your system.

 

It's going into the engine and radiator. There were probably air pockets that wouldn't let you completely fill the system until the air dispipated. Best is to use a Lisle funnel

 

A Lisle funnel will work fine, but there really is no need to buy anything to get this done properly.