You can add to the radiator, but it is a bit more dangerous, with spit backs so it is best to add to the reservoir. As the engine heats up, the hot water pressure will push water out into the reservoir where it remains until the engine cools down. The cold engine then creates a Vacuum, which pulls the water out of the reservoir and into the engine, maintaining the level. This goes on all the time you are driving.
So by adding to the reservoir, you put in water ( anti freeze, not water) and this will then be pulled into the engine once it starts to cool down. ( with the CAP ON the radiator).
Adding coolant to the reservoir and keeping it between the top and bottom lines, will also burp the system but it might take a bit longer, as it has to wait until the coolant temp is high and the pressure is high enough to open the cap vent to the reservoir. This then has to wait until the engine is cool enough to pull it back in. and so, more time is needed.
Depends how big the air bubbles are and where they get stuck. The temperature could become erratic, and then get a little hotter or a lot hotter depending on how bad the issue is. So don't take any chances and just bleed it. But if there are a few tiny air bubbles remaining then don't worry about it too much.
Yep. Turn heater on HI, fill radiator, and wait. When thermostat opens, you will see water circulating in rad., and coolant will be warm. Top off rad. and overflow tank. If air still in system, park on slope facing up, and repeat.
It can, or it may work fine or the head may warp (Subaru 2.5L are notorious for that). It would really help if we knew what make, model, and year this is.
That pretty much sums it up!
yes it will
