Chrysler 68138644AA Engine Oil Pump

The replacements oils pumps on earlier models may be necessitated because of a collapsing oil pressure relief valve and spring for on these early model pumps an expansion plug is installed in lieu of a threaded plug to seal the oil pressure relief valve and spring within the pump; it is best to contact a dealer parts department or a qualified automotive repair facility for the right one. To install the pump, firstly require removing the primary timing chain and crankshaft sprocket in a manner that the bearing and marks of the sprocket are rightly aligned with the marks on the outer face of the oil pump housing without rotating the crankshaft from this position that is approximately 60 degree after top dead centre. Then drain the oil, and then you can uninstall the oil pan, oil pump pick-up tube and the bolts that connects the oil pump to the engine block from the front side of the vehicle's engine. Carefully push the oil pump housing to the right to free the dowel pins and then take-off the housing from the engine. As disassembled dissonance put on the lip of the screw for the front cover to the housing of the oil pump and decide all of the components into the solvent and look for the wear and major scratch. Take off the oil pressure regulator cap, washer, spring and valve and inspect the oil pressure relief valve sliding surface and the valve spring; if either of the two are worn out, change both as a set. This clearance can be measured with a feeler gauge and a micrometer or a dial caliper checking cover flatness, outer rotor diameter and thickness, inner rotor thickness and other clearances; if the clearance exceeds the standard, the entire unit of the oil pump must be replaced. Apply the petroleum jelly to the pump and assemble the oil pump, tighten all the fasteners to the required torque, put the oil pressure regulator valve, spring, and washer in the cap and tighten it. To install reverse the sequence above: to align the flats in the rotor with the flats on the crankshaft, fit the pump-to-block bolts, tighten them to the specified torque and then the pump will fit back in position.

Next, remove the oil pan, followed by the oil pump pick-up tube and the oil pump-to-engine block bolts from the front of the engine. Gently pry the oil pump housing outward to clear the dowel pins and remove it from the engine.

Replace the pump, ensuring the inner rotor is installed with the mark facing up.

Replace the assembly if any parts are damaged.

The remainder of the installation follows the reverse order of removal.

Disconnect the oil pump solenoid electrical connector from the engine by depressing the locking tab and pushing the connector into the block, maneuvering it around the tensioner mounting bolt.

Install the inner rotor and measure the clearance between the lobes of the inner and outer rotors; if it exceeds the specified value, replace the pump, ensuring the inner rotor is installed with the mark facing up.

Drain the engine oil, then remove the lower splash shield fasteners and the splash shield.

Make reference marks on the chain and oil pump gear, hold the gear to prevent movement, and remove the T45 Torx mounting bolt and the gear.

Place the timing chain over the crankshaft sprocket, aligning the plated link with the timing mark or previously made marks. Lift the BSM and place the drive sprocket into the timing chain, aligning the plated link with the timing mark on the drive gear.

The first step is to take off the oil pan and pick-up assemblies.

Install a new O-ring in the oil pump pick-up opening, lubricate it, and carefully work the pick-up tube into the pump, securing it with the retaining bolt.

Remove the bolts securing the primary timing chain tensioner/oil pump housing.

Remove the four mounting bolts and remove the oil pump assembly from the gear case.

The oil pump on the Hemi engine is available only as a complete unit.