PUMP, Transmission Oil
DESCRIPTION
DESCRIPTION
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The oil pump (2) (crescent-type pump) is installed in the bellhousing behind the torque converter and is driven by the drive flange of the torque converter. The pump creates the oil pressure required for the hydraulic procedures.
OPERATION
OPERATION
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When the engine is running, the oil is pumped through the inlet chamber (5) along the upper and lower side of the crescent (1) to the pressure chamber (6) of the housing. The meshing of the teeth prevents oil flowing from the delivery side to the intake side. An external gear (3) is eccentrically mounted in the pump housing. The external gear is driven by the internal gear (4) which is connected to the torque converter hub.
DISASSEMBLY
DISASSEMBLY
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CLEANING
CLEANING
Clean pump and support components with solvent and dry them with compressed air.
INSPECTION
INSPECTION
Before measuring any oil pump components, perform a thorough visual inspection of all the components. If any sign of scoring, scratches, or other damage is seen, replace the oil pump as an assembly.
SIDE CLEARANCE
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Side clearance is the difference between the thickness of the pump gears and the depth of the pocket in the pump housing. Side clearance can be measured by laying a flat plate (1) across the mounting face of the pump housing, and measuring the distance between the plate and the gears with a feeler gauge (2).
Acceptable side clearance:
TIP CLEARANCE
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Tip clearance is the difference between the tip diameters of the gear teeth and the corresponding diameters of the pocket in the pump housing.
Tip clearance for the inner gear can be checked by moving the inner gear into tight mesh (2) with the outer gear as shown. Clearance between the ID of the crescent feature of the housing and the OD of the teeth of the inner gear (3) should then me measured at a point 37 mm (1.45 in.) from the corner of the crescent (1) feature, as shown below.
Acceptable tip clearance for inner gear:
ASSEMBLY
ASSEMBLY
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