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Pressure Test

  1. Note pressure reading with valve open and engine idling. Pressure should be 80-125 psi (6-9 kg/cm2 ). If pressure is above 200 psi (14 kg/cm2 ), check hoses for restrictions and poppet valve for proper assembly.
  2. Completely close and reopen gate valve 3 times. Record highest reading each time. DO NOT close valve longer than 5 seconds. Readings should be within specifications. On "G", "P" and "R" & "V" Series, see Fig 1 . On all other models, see PRESSURE TEST SPECIFICATIONS TABLE.
  3. If readings are within specifications and within 50 psi (4 kg/cm2 ) of each other, pump is operating properly. On "G", "P" and "R" & "V" Series, see Fig 1 . On all other models, see PRESSURE TEST SPECIFICATIONS table.
  4. If readings are higher than specifications and not within 50 psi (4 kg/cm2 ) of each other, flow control valve in pump is sticking. Remove and clean or replace flow control valve.
  5. If pressure is constant but more than 100 psi (7 kg/cm2 ) below specifications, clean or replace flow control valve in pump. If readings are still low, replace pump.
  6. If pump is within specifications, open valve, and turn steering wheel from right to left stops. Record pressure. DO NOT hold wheel against either stop longer than 5 seconds.
  7. Pressure should be within specifications. On "G", "P" and "R" & "V" Series, see Fig 1 . On all other models, see PRESSURE TEST SPECIFICATIONS TABLE. If pressure is low, steering gear is leaking internally and must be repaired.
Fig 1: Pump Pressure Specifications ( "G", "P" and "R" & "V" Series)
G117434Courtesy of GENERAL MOTORS CORP.
PRESSURE TEST SPECIFICATIONS

Application Idle Pressure - psi (kg/cm2 ) Relief Pressure - psi (kg/cm2 )
Astro & Safari 80-125 (6-9) 1250-1350 (87-95)
C15/25 & "K" Series 80-125 (6-9) 1200-1300 (84-91)
C35 80-125 (6-9) 1350-1450 (95-102)
C35 (W/ Hydro-Boost) 80-125 (6-9) 1465-1515 (103-106)
"S" & "T" Series 80-125 (6-9) 1100-1200 (77-84)
BELT TENSION (Tension in Lbs. Using Burroughs Tension Gauge)

Application New Belt Used Belt
Serpentine Belt (1) (1)
"V" Belt 146 67
(1) Serpentine belts are equipped with self-tensioner and no adjustment is required.