Help needed with 4x5 camera

[Boris Liberman]

Hi!

A friend of mine enabled himself with 4x5 camera with Schneider 
Kreuznach Symmar 1:5,6 / 210 lens. This camera/lens has Synchro Compur 
#1 shutter. Unfortunately the shutter needs repair. Ideally I would 
like to get technical/repair manual or at least a sketch of the 
shutter using which he would be able to repair it. Also on the lens 
there is green text which goes like this: "1:12/370". Any clue as to 
its meaning?!

Any help would be greately appreciated by me and by him as well.

Thanks.

Boris