Losing Coolant very quickly

Hello,

I recently had my car serviced (2000 BMW E39 523i SE) and when I got home, the coolant level warning came on. I do not use it much but checked the level and it was very low, so I topped it up, thinking "Not much of a service if they didn't even flush the coolant system and refill it!)

Anyway, I just used it again and the coolant warning came on again. I checked it and it was completely empty. I filled it and went for a short drive. Within 30 seconds the warning came on again, I pulled over and checked the coolant level and it was completely empty again. There is clearly a massive leak somewhere. There is no coolant residue anywhere that I can see.

Has anybody had any experience with this or any idea what it may be?!

Any help would be appreciated.

What does the temperature gauge read?
Could be an electrical error.

Wait, you filled the expansion tank? refilled and there is not dripping visible?

Temp is fine but the expansion tank seems to empty almost immediately - I cannot see it leaking out however!

Do NOT drive the car.
Search forum for "Cooling Overhaul" to find answer.

PS: Check your engine oil dipstick for any trace of coolant (milky color).

I had a similar problem. Check the top radiator hose that connects at your radiator and resivoir tank under the cap by your filter box then leads over to the thremometer. Mine was coming apart from where the rubber hose meets the plastic fitting. I had little to no visible fluid leak but allot of steam as the fluid burnt off and evaporated. I changed that and no more problem.

Sent from my LS670 using Bimmer App

Originally Posted by 7945049

Hello,

I recently had my car serviced (2000 BMW E39 523i SE) and when I got home, the coolant level warning came on. I do not use it much but checked the level and it was very low, so I topped it up, thinking "Not much of a service if they didn't even flush the coolant system and refill it!)

Anyway, I just used it again and the coolant warning came on again. I checked it and it was completely empty. I filled it and went for a short drive. Within 30 seconds the warning came on again, I pulled over and checked the coolant level and it was completely empty again. There is clearly a massive leak somewhere. There is no coolant residue anywhere that I can see.

Has anybody had any experience with this or any idea what it may be?!

Any help would be appreciated.

What type of service was performed? If the cooling system was flushed or even drained and refilled, it's possible the dealer did not complete purging air from the system. Air in the system needs to be replaced. Having said that, 2 empty expansion tanks seems like a lot of fluid.

Sounds like blown headgaskit.

Originally Posted by boyhowdy985

Sounds like blown headgaskit.

If it was a head gasket and using that much coolant the engine would be running like crap.

Is the CEL on?
Pull the oil dip stick and see if the oil lever is much higher than normal.
The coolant has to be going somewhere.
Hope that the system wasn't bleed properly like 540sport said and that coolant is just replacing the trapped air.

Could be one of 2 things in my opinion:
1.) Had a huge air bubble, and after "regurgitating" the coolant was low. Still more air in the system, had to be purged. Maybe the indy wasn't a BMW "specialist"
2.) Car was serviced - if any of the cooling components were changed, I would look hard right there. I had an issue with a bad expansion tank that was leaking like a sieve - brand new. If no component was changed, a hose might have come slightly undone (which I doubt due to the high pressure - it should pop right out), or damage to one of the plastic components has occurred. A small crack enough to open up as soon as the coolant reaches operating temperature and pressure forms, expanding the said crack.

If the cooling components are the original ones, as CNN suggested, change all hoses, radiator, WP, T-stat, pulleys, exp tank & radiator. Don't take shortcuts if you want to keep the car.

Originally Posted by doru

Don't take shortcuts if you want to keep the car.

The last 50 people who did take shortcuts ...
(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) (13) (14) (15) (16) (17) (18) (19) (20) (21) (22) (23) (24) (25) (26) (27) (28) (29) (30) (31) (32) (33) (34) (35) (36) (37) (38) (39) (40) (41) (42) (43) (44) (45) (46) (47) (48) (49) (50)

To the OP:

Take a look at this thread for all the places where the cooling system can fail on the E39 ... and then doublecheck yours:
- Pictorial look at typical E39 cooling system failure modes (1)

When you do your overhaul, read this thread for the parts to replace:
- Complete cooling system overhaul recommended parts list (1)

Dont mean to hi-jack this thread but I'm having almost the same issues.

I had my cooling overhaul done about 3 months ago... everything is running fine but a couple of days ago I checked the coolant level in the expansion tank and I saw that it was almost empty. I filled it up and the next day it was half way. I filled it again and the next day it was half way again.

I checked the oil cap and dip stick and it looks fine. I don't see any visible leaks anywhere and the car is not overheating.

Anyone has any ideas whats going on with my car?

Are you getting heat from both sides of the cabin heater? If not there is air in the system.
Keep an eye on the level in the tank. If it's just trapped air you shouldn't have to add more in a day or two.