I asked this question once before and the only answer I got was read the manual. Nothing in the manual says how to purge the air when changing the coolant. It says add coolant slowly. Is there another way to know you don't have any air pockets in the cooling system after changing the coolant. I have an 02 Outback. Thanks Jeff
Yeah, you don't blow head gaskets... :-)
Just kidding, I usually run the vehicle with the rad cap off for a few minutes and watch for the level to drop. If it drops then you know an air bubble just escaped. After it sits level for a few solid minutes, you have them all out. It doesn't hurt to elevate the front of the vehicle to make sure the rad cap is the highest point of exit either.
-Kurt
Jeff wrote:
Actually, this topic is discussed often on the group. Make sure the radiator vent valve is removed while adding the coolant (this valve is a small one located at the upper left part of the radiator when facing the engine). Also add coolant very slowly. I also like to bounce the car up and down to help 'jiggle' the water/air. In some cases, running the engine and removing the water heater hose going to the firewall can help. I'm sure there are other methods used as well. John
Thanks actually I looked for the valve before but couldn't find it. Jeff
Thanks
My '90 Legacy has the vent valve as does my '02 Outback VDC Sedan. I agree with burping the engine, as much as possible. I don't trust using the overflow bottle at all. I don't know why... just seems better to check the actually radiator level, at least for me. You cannot be too careful in taking your time when refilling the cooling system in a horizontal engine design. John
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