[Bimmerfan]

I saw some machine at my local Mobil service station that is able to drain your old engine coolant completely just by inserting a hose/cap from where you fill it up and also put in the new coolant from the same place. No mess and it was done in 15mins. Weird that they were doing it with the motor running while all the coolant was being drained. Is this safe to do on the E46?

 

[Jack_Smackus]

Whoa. I guess as long as the coolant isn't out of the engine for very long you could theoretically do it. 15 minutes though? That seams like a long time to do all that.

 

[tim330i]

I would guess they were doing it with the car running so the water pump could circulate the old coolant out of the block and the new coolant in.

I would assume it is safe, but does it give you the best results? I wouldn't be so sure.

Tim

 

[monkeyx328]

i did that at my friends EZ Lube work place... seems fine to me