Level of engine output is not related to water consumption at all, you are not doing anything wrong. It's too soon after the leaking radiator to assume that the engine is consuming water. .4 liter is not much to add at all. Some engines hide air pockets within them and it takes weeks to purge all the air out of the sealed cooling system.
After such a workout of your radiator's air purging system, it might now be defeated by some trash under the radiator cap's central venting valve. If this valve is held open by trash in the coolant, the warming engine will just push out water instead of building pressure as it very much NEEDS to. This will cause water consumption when there is really nothing at all wrong. This is also the most likely situation that you are in right now. Remove and clean your radiator overflow tank to eliminate the valve sticking trash and keep an eye on that little valve on your radiator cap.
I often find the valve over sprung such that it won't even work properly on a new cap. I then pry the unit off the cap with the twist of the handle of a cresent wrench and then I cut and stretch the spring pulling that valve shut too hard until I can lift it with my lips easily. The entire unit is only held onto the radiator cap proper with four pin pressed divets around the circumfrence of the black rubbered main unit of the radiator cap. Why they don't fall apart all the time is a wonder to me. At any rate it seems you can't buy working parts sometimes so I include the how to on fixing the vent/air purging valve. It is central to an air free cooling system and an air free cooling system can NOT rust, which is why they are so desirable in the first place. That and pressurized coolant won't boil over until it gets really extra hot. Please ONLY check your radiator cap when the engine is cool.
Jun 21, 2009 |
2007 BMW 335i Coupe