need coolant changing advice......

[tim s]

when i purchased my 540i/a last year i did not about the leaking heater core until i owned it a month. it started to smell worse, but no water out the vents. it was leaving a slimy film on the window. so at that time i added the coolant system sealer that they use in jaguars. it slowly smelled less & less. i have not smelled it in 2 months now, but i am due for a coolant flush. the previous owner used prestone. i want to use bmw coolant, but i am concerned that this will open the leak up again when i do the change.

how much of a risk am i taking in changing it or should i let it go???

thanks
tim s.

[632 Regal]

dont use any caustic flush addatives and simply drain, flush with water and refill with new antifreeze and diastilled water. I would flush with water a couple times though since your probably not going to remove the drivers side block plug. Drain, close it back up fill withe water, run for a few, drain, close up fill run, drain then do the new fluids. Figure out the capacity first and add half that amount of antifreeze first before the distilled water incase there is still water in the block. No secrets here as to bleeding as in the 6 cyls.

[tim s]

after all if it is going to leak sooner or later, i would rather have it leak in the garage than on the road.
thanks
tim s.