In normal operation the stop rod is facing towards the engine.
In “limp home“ mode the stop plate (with stop rod ) key #47 is turned 180 degrees so the stop rod is facing away from the engine. In this position the stop rod doesn’t allow the piston to travel full stroke limiting the flow from the hydraulic pump. This limp home mode applies to Hitachi excavator models EX 100/120/200/220 (-2 or-3) and Deere excavators 490E and 790E (high and low serial # ‘s)
The screenshot below shows stop plate (with stop rod) #47 in normal position.
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