There is a new tool that I have used for this and it is the best tool I have used in years. It is called an AirLift. It uses shop air to vacuum down the cooling system, then you hold it for a while and see if it leaks down, if so you still have a leak...If not, drop the hose in the coolant tank and it pulls the coolant in in 15 seconds!!!!!! After the coolant is in, the system IS purged. I have not seen it fail yet!!
1992 500E (very soon I hope
1981 280GE SWB
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