BMW 630i coolant issues
Discussion
Hi all
Continuing my form with having coolant issues on every used car I have ever owned, my latest project is baffling me.
My 630i started throwing up coolant back out the over flow about 6 months ago, with it I had a water pump speed deviation code and this tied in with the electric water pump on its way out. The car never over heated though.
Without delay I had a new electric water pump and stat fitted, driven by the fear of it failing completely.
The car probably went a few weeks after without using to much coolant, the water pump speed deviation code has never returned, but after a while I have found myself in the habit of topping it up every couple of days again. The car never over heats, so surely the pump must be working? But you can clearly see dried coolant round the rim of the vessel and assuming its going out the over flow hole.
Any ideas on what could still be causing the escape of coolant out the over flow after a new pump and stat?
Continuing my form with having coolant issues on every used car I have ever owned, my latest project is baffling me.
My 630i started throwing up coolant back out the over flow about 6 months ago, with it I had a water pump speed deviation code and this tied in with the electric water pump on its way out. The car never over heated though.
Without delay I had a new electric water pump and stat fitted, driven by the fear of it failing completely.
The car probably went a few weeks after without using to much coolant, the water pump speed deviation code has never returned, but after a while I have found myself in the habit of topping it up every couple of days again. The car never over heats, so surely the pump must be working? But you can clearly see dried coolant round the rim of the vessel and assuming its going out the over flow hole.
Any ideas on what could still be causing the escape of coolant out the over flow after a new pump and stat?
Do you have any oil in coolant contamination(or vice versa)? As a failing oil filter housing can cause this.
Otherwise it’s due to too much pressure, which will usually be be caused by either the coolant overheating(maybe not bled correctly?) or a failed head gasket. My first point of call would be to do a sniff test. Although head gasket failures are very rare as generally you’d need to overheat the engine for at least 5-10 minutes to cause, they do happen.
Otherwise it’s due to too much pressure, which will usually be be caused by either the coolant overheating(maybe not bled correctly?) or a failed head gasket. My first point of call would be to do a sniff test. Although head gasket failures are very rare as generally you’d need to overheat the engine for at least 5-10 minutes to cause, they do happen.
Collectingbrass said:
How is the bottom of the radiator? Straight & true or starting to warp?
I will check that out, is that the forward most facing rad, I.e you can see it through the front bumper?The AC condenser was done last year, but I assume that's behind the rad? If so I will check that in the day light.
Did the secret menu tonight to monitor the water temperature on the way home, temp didnt fo any higher than picturede
So a few more questions 
Do you get a low coolant warning or just topping up after checking coolant levels?
Secondly, it may sound basic, but are you following the max coolant level diagram/instruction that is printed on the top of the expansion tank? Only reason I say this is because I’ve worked on many BMs, the float position is different for various models/engines, so I always have to double check the diagram.
Do you get a low coolant warning or just topping up after checking coolant levels?
Secondly, it may sound basic, but are you following the max coolant level diagram/instruction that is printed on the top of the expansion tank? Only reason I say this is because I’ve worked on many BMs, the float position is different for various models/engines, so I always have to double check the diagram.
Marc p said:
So a few more questions
Do you get a low coolant warning or just topping up after checking coolant levels?
Never left it to go to the light, just keep topping up
Secondly, it may sound basic, but are you following the max coolant level diagram/instruction that is printed on the top of the expansion tank? Only reason I say this is because I’ve worked on many BMs, the float position is different for various models/engines, so I always have to double check the diagram.
Yes following the diagram on the side of the vessel, Do you get a low coolant warning or just topping up after checking coolant levels?
Never left it to go to the light, just keep topping up
Secondly, it may sound basic, but are you following the max coolant level diagram/instruction that is printed on the top of the expansion tank? Only reason I say this is because I’ve worked on many BMs, the float position is different for various models/engines, so I always have to double check the diagram.
Quavers said:
I replaced the expansion tank on my e60 545 due to a broken float. There was also evidence of coolant escaping past the cap.
As soon as I replaced it one of the small hoses popped. The new cap was holding pressure - unlike the old one.
Sounds feasible, I have ordered a new cap just to rule that out. Thanks all, will report back. I'm daily driving it again so should see the results quite quickly.As soon as I replaced it one of the small hoses popped. The new cap was holding pressure - unlike the old one.
Well, as an update the car showed me what was wrong in the end. The radiator split and dumped everything in the car park, still trying to get it recovered.
Still unsure if a failing radiator would have caused coolant to back up? Oh well, can't really moan as the rad is stamped March 2008 so it's had a good innings.
Still unsure if a failing radiator would have caused coolant to back up? Oh well, can't really moan as the rad is stamped March 2008 so it's had a good innings.
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