Red:

Did the engine come with an injection pump installed, or did you install the old one yourself?

Have you tried disconnecting the EGR valve actuating vac line? A stuck EGR will cause all sorts of problems, but that big cloud of inky black heavy smoke is a classic, especially if at low speed and you floor it.

How much did you get with the engine? Was it complete with head and manifolds, or did you only get a long block, had used the old head, manifolds, injection pump, starter, etc?

Something is definitely wrong here, it should run like new.

Peter

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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!