Complete E39 M54 cooling system overhaul

[StephenVA]

Remember you are looking at a 528 application. The process is similar but the Thermostat area and hoses are different. The water heater switches are on the frame rail near the steering column. Setting to "HOT" allows you to back flush the heater box in the dash so you get every bit of material out of the system. Necessary? Depends on how bad the coolant is. 90% just drain and refill with no issues reported.

[rickadootrd]

I never bother with that, but then again, my coolant is clean as hell as I always change it every year, distilled water and BMW coolant.

Remember you are looking at a 528 application. The process is similar but the Thermostat area and hoses are different. The water heater switches are on the frame rail near the steering column. Setting to "HOT" allows you to back flush the heater box in the dash so you get every bit of material out of the system. Necessary? Depends on how bad the coolant is. 90% just drain and refill with no issues reported.

Yes, I know Steve. I should probably do the flush just to get the green coolant out that the original/previous owner's shop used... I like my coolant BMW blue lol

[BimmrMeUpSnotty]

I ran green Preston's in my old green wagon that I wrecked, for close to 4 years, never had a problem, just make sure you do a full flush then if you are switching back.

[babla]

Hello,

Jumping into this topic as I have to replace the radiator on my 2001 530i automatic, EU spec (Italy). I have previously replaced all the coolant hoses after I have noticed a lot of coolant lost under the car in the garage (luckily). I did not see any need to replace the radiator back then, but now - 2 months later - i have noticed coolant loss in the driver side after the engine is heated up. It seems that there is a loss from the radiator. I guess I should have listened to the E39 community and replace the radiator as well when noticed weakness in the system

On my previous replacement - I have filled up my cooling system with green alu-safe coolant. I was advised by my mechanic who changed the coolant that any blue or green would be suitable to fill up. There were no issues since then with the cooling capacity or any anomalies, but now that i will have to drain the coolant again, I would like to fill in original BMW coolant.


My questions are
1. Is there any way to completely drain the coolant - including the one from the engine - without undoing the engine bolt - near cylinder 2? I do not have a lot of space for this where I am working on my car - and I was thinking to somehow drain all the liquid only using front accessible radiator drain / hoses. I am open to any of your suggestions.
2. I have ordered MAHLE Radiator for replacement - anyone has any feedback on using this? seems to be the same manufacturer as BEHR?
3. I cannot find the BMW 1 Gallon bottle coolant in Europe but only BMW 83512355290 - anyone has any experience with this?


Thank you!


More details about my car:
2001 530i - automatic. 120k KM (~75k mls)
Recently changed in the cooling system
- all cooling hoses (not plastic pipes, not cabin side hoses - they are looking good)
- water pump - with Continental metal pump
- all pulleys / rolls
- expansion tank - after developing cracks