Injection Pump types?

[Zanimat]

I'm a new owner of an '88 300D Auto & have been studying the Haynes manual to try & understand the way the fuel system works. It refers to the use of a vacuum valve & solenoid to shut off the fuel to the injector pump. Despite diligent search, I cannot locate either of these components & wonder if some pumps may be electrically controlled, as there are 2 wires emerging from the rear of the pump casing. Any guidance would be appreciated.....

 

[dieselman]

The pump should eb mechanical on this car. The vacuum shutoff is at the back of the pump on the top. When vacuum is applied the control rack moves to the stop position.
The wires feed the electric stop solenoid.