Hi,

well, German Diesels were started by means of the compressed air.
There was a dedicated installation (see here:
[uboatarchive.net]
which admitted the compressed air through the valve in the cylinder head to each cylinder in proper sequence. As a result, the crankshaft started turning, and finally, the fuel was admitted and ignition occurred.


In general this system was similar to the one used on US submarines. Detailed description you can find here:
[www.maritime.org]

So generally, if compressed air was available, the engines could be started without electrical power.

Worse, if there was no compressed air. Then you have to charge air-flasks, either with electric compressor, or with Diesel compressor.

There was also another way to start engines without compressed air (but in this case electric power is strongly needed). One can use electric motors as a starter, after engaging the main clutches between motors and engines, motors start to turn crankshaft (instead of compressed air).

--
Regards
Maciek


[www.tvre.org]