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Transmission operates normally in one direction only....................................................................................................25
System will not operate in either direction.......................................................................................................................... 26
Low motor output torque...........................................................................................................................................................26
Improper motor output speed..................................................................................................................................................26
System noise or vibration........................................................................................................................................................... 27
System response is sluggish...................................................................................................................................................... 27
Adjustments
Standard procedures, inspections, and adjustments....................................................................................................... 28
Adjustments.....................................................................................................................................................................................28
Charge pressure relief valve adjustment...............................................................................................................................28
Multi-function valve pressure adjustment............................................................................................................................30
Engaging the bypass function.................................................................................................................................................. 31
Pressure override (POR) valve pressure adjustment (option for 180 frame size)....................................................32
Displacement limiter adjustment............................................................................................................................................ 33
Standard manual displacement control (MDC) adjustment.......................................................................................... 33
Non-linear manual displacement control (MDC)............................................................................................................... 34
MDC Neutral start switch (NSS) adjustments.......................................................................................................................35
Checking switch continuity........................................................................................................................................................38
Hydraulic displacement control (HDC) and electric displacement control (EDC) adjustment..........................39
Speed sensor adjustment........................................................................................................................................................... 40
Minor repair
Standard procedures.................................................................................................................................................................... 42
Removing the pump................................................................................................................................................................42
Shaft seal and shaft replacement.............................................................................................................................................42
Multi-function valve cartridges.................................................................................................................................................44
Multi-function valve cartridges - pre 1988............................................................................................................................46
Pressure override valve (option for 180 frame size).......................................................................................................... 47
Charge pressure relief valve.......................................................................................................................................................48
Adding an Auxiliary pad to a pump previously without one.........................................................................................50
Auxiliary pad.................................................................................................................................................................................... 51
Charge pump...................................................................................................................................................................................52
Integral charge pressure filter replacement.........................................................................................................................55
Pump control cover plate........................................................................................................................................................... 56
Displacement control orifices....................................................................................................................................................57
Displacement control orifice check valve............................................................................................................................. 57
Displacement control adapter plate (early production 130 pumps only).................................................................58
Manual displacement control (MDC)......................................................................................................................................59
Solenoid override valve for MDC..............................................................................................................................................60
Solenoid override valve for MDC with pressure released brake...................................................................................61
Hydraulic and electric displacement controls..................................................................................................................... 62
Pressure control pilot (PCP) for electric displacement control (EDC)..........................................................................63
3-Position (FNR) electric control...............................................................................................................................................63
Displacement control filter screens.........................................................................................................................................65
Speed sensor................................................................................................................................................................................... 66
Torque chart
Fastener size and torque chart..................................................................................................................................................68
Plug size and torque chart..........................................................................................................................................................69
Fasteners and plugs...................................................................................................................................................................... 70
Service Manual
Series 90 Pumps
Contents
4
520L0818 • Rev 0101 • August 2015