[schwarze-man]

The first two documents above were originally Daimler-Benz publications of the Motor Handbuch and the Instandsetzungsvorscriften. Later, these were slightly modified and issued as the service documents D. (Luft) T. 3605 etc.
This next document seems to be a Daimler-Benz manual that was designed for repair and overhaul centres. This is the Reparatur Anleitung DB 605 A-B (Repair guide).
The previous Instand covers work to overhaul the engines within the normal wear and usage. The Reparatur Anleitung DB 605 A-B is designed for repair of damages beyond the normal wear and tear but, it also includes modifications and updates of the engine (of which there are a considerable number) and notes about recording engine overhauls. The Reparatur Anleitung DB 605 A-B comes in developing versions as the engine is developed, I have two versions, and there would have been more. However, this is not the end of the technical documentation for the DB 605 A. In Summer 1942 the newly introduced DB 605 was restricted to reduced power due to engine failures. These failures were mainly due to combinations of Exhaust valve metal problems, poor Injection Nozzle spray pattern, Lubrication weakness due to low oil flow and thin-crown Pistons. Operational instructions were issued and limitations imposed, then lifted when remedial work was completed. These improvements are seen in the later issues of the Reparatur Anleitung DB 605 A-B.
Before we move-on to consider the DB 605 A-B engine life, it is worth considering the overall Repair/Servicing situation. Engines often suffered damage or malfunction within the normal Military use. Engines that required repair at overhaul facilities would be assessed for the need to incorporate various updates and servicing. There would be little point in just repairing an engine with a burn't exhaust valve if it was say, half-way to a Teiluberholung.
There will have been guidelines on the management of engine repair/overhaul but, there is no guidance on that or, on engine life extensions as a policy in any of these documents. edit. *However, as of 4/11/22 I have seen RLM docs with airframe and engine life extension information and this will be covered in due course.*
Next, I am going to cover the servicing-cycle examples.

Cheers

SM