Checking/Topping Off Fluid Level In Hydraulic System: S6S420G/SMG
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Turn on ignition. Press brake pedal. Move selector lever from position "0" to "R" or "0" to "E" until hydraulic pump is activated. Wait until hydraulic pump shuts down. Open expansion tank (1). See Fig 1. Fill expansion tank up to MAX marking (2) on dipstick (1). See Fig 2. Check with dipstick on cap by screwing in cap.