I'm replacing the radiator on the '90 560SEL (yep - broke at the neck).

Any learned opinions on whether to do the acid flush A) with the old radiator on then replace or B) flush with new one in place?

I'm thinking B) - no sense loosening up whatever is in the old one...

Kevin

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"Dangerous with a wrench...and not smart enough to know it"

Stable (in order of acqusition):
'84 500SL, 280SEL (Euros)
'77 280SE. '90 560SEL
'79 450SEL 6.9,
'95 C280 (totalled by daughter 8/07)
'81 280SL (rescued) '88 300CE
'86 560SEC '95 C36
'01 CL55

DD's: '04 S500 4Matic (SWMBO)
'04 F150 Crew