'lectronic injection pump that tends to fail, usually due to rust/metal contamination in the fuel filter/tank, but they do have other issues of failure. check the harmonic balancer/dampener, there is a pulley that bolts to front that is rubber dampened, the rubber deteriorates and the pulley starts slapping around, sounds like a rod knock ( loudly) the balancer itself can fail as well.
vacuum solenoid for turbo waste gates fails, causing waste gate to not close, ( look for heavier than normal black smoke and low power on acceleration )
Fuel Solenoid Driver (FSD) black box mounted to side of injection pump tends to fail from excess heat, there are kits that relocate, and/or add a heat sink, mixed results. ( FYI, if this box gets changed, be aware of the resistor that needs to be removed from old unit and installed on new, and there are different values available )
glow plugs, PITA to test and change ( cyls 6-8 on right rear especially )
cyl head gaskets tend to fail, usually due to coolant cavitation, which also causes block/head erosion, and there was an issue of block porosity. Coolant would weep thru casting into oil, causing bearing issues ( at 200k, I doubt this is an issue )
when they run, they run well, but were never power houses, they are quiet, and reasonably reliable, decent milage 15-18 unloaded driven sanely
oh, and the "small leak" may well be an indication it has a reasonable amount of blowby, which could be a near end of useful life issue
