I know for a fact that the delivery valve seals on the newly-acquired 1987 300TD need to be replaced, so that's one of the first things I'm doing. I noticed a mildly rough idle and a bit of nailing under mild load. Is it possible that these are symptoms of the bad delivery valve seals?

Thanks.

__________________
14 E250 Bluetec 4Matic "Sinclair", Palladium Silver on Black, 159k miles
06 E320 CDI "Rutherford", Black on Tan, 179k mi, Stage 1 tune, tuned TCU
91 300D "Otis", Smoke Silver on Tan, 145k mi, wastegate conversion, ALDA delete

19 Honda CR-V EX 77k mi
Fourteen other MB's owned and sold
1961 Very Tolerant Wife