Hello again!
The hydraulic pump is driven by a short shaft from the front of the engine crankshaft. The main hydraulic pump is situated just ahead of the radiator. The pump for the hydrostatic steering is mounted on the front RHS. of the engine, driven by the timing gears. Thus, engine not running = no hydraulic power.
You are welcome to ask more questions, but Mr. Toad speaks only from personal experiences, and doesn't claim to be an expert!
Mr. Toad
May 2009