lost off power and black smoke

I suspect some coking of your EGR system and Turbo. This is a fairly common issue and requires some good cleaning, the installation of a baffle kit for the EGR system, and probable overhaul of your Turbocharger central housing rotating assembly (CHRA). The unison ring in the turbo is probably frozen too. These are very common occurances with this engine. Further, to prevent coking, it's a good practice to use some cetane boost with a fuel fill up to help burn the Diesel more completely.