Thanks guys. I'd planned on borrowing a pressure tester shortly (have a friend in the radiator business), but with a whiff of coolant at the water pump, I'm pretty sure that's the problem.
215,000 miles and I don't know when it was replaced last, not bad.
As I said, now is the time since I gotta take everything else off anyway.
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!