I'm putting in a new rad into a 87 300D, and want to flush the system before refilling it with MB fluid.

Would anyone NOT recommend bypassing the rad to do a flush, I don't want to flush with the new rad in place, as it will get contaminated, and I don't want to flush with the old rad in place, as it will take much longer with all the debris in the old rad and probably just carry those contaminets into the engine/head during the flush???

I will be keeping an eye on the Temp Guage the entire time so that it does not climb above 100C during the Flush W/O a rad.

I'm not going to use Cirtic Acid as I fear it will attack my already volnurable head gasket, instead a Regular Prestone flush is what I'll be using.

Let me know what you think...