Lexus 15103-31050 Rotor Set, Oil Pump

To remove the oil pump, relieve the valve plug, spring, and valve. Also, loosen and remove the oil pump cover bolts and cover, and remove the drive and driven rotor. Inspect all parts for damage. Also, apply petroleum jelly to the rotors and place them in the timing chain cover with pump marks out. Lubricate and insert the oil pressure relief valve and spring, tighten the plug, and reinstall the timing chain cover.

To begin with, to remove the oil pump, you can detach the timing chain and crankshaft sprocket. You can alter the crankshaft's position and undo the oil pump drive chain as well as the sprockets. Clean the pump body and engine block surfaces, removing old gasket material. Inspect the oil pump and drive chain for wear.

On 2008 and later models, the oil pump cannot be serviced separately from the timing chain cover; if defective, both must be replaced as a unit. To remove the oil pump, first take off the timing chain and crankshaft sprocket, then remove the oil pump drive chain and sprockets by rotating the engine 90 degrees counterclockwise from TDC, setting the crankshaft key to the left horizontal position, and loosening the retaining bolt while locking the lower gear in place. Next, detach the oil pump body by removing three bolts, prying carefully if necessary, and clean all traces of sealant and old gasket material from the pump body and engine block. Inspect the oil pump and chain for wear and damage; if there are signs of wear, replacement is recommended. Measure the diameter of the sprockets across the chain rollers, and if below the minimum diameter, replace the chain and sprockets. Check the oil jet for blockages to prevent excessive wear. For installation, lubricate the pump cavity with clean engine oil, position the oil pump with a new gasket against the block, and install the mounting bolts, tightening them in a crisscross pattern. Install the drive chain and sprockets, ensuring the colored links align with the marks on the drive gears, then tighten the lower drive sprocket retaining bolt. Reinstall the remaining parts in reverse order, add oil to the proper level, start the engine, and check for oil pressure and leaks.

The oil pump is mounted inside the timing chain cover and therefore to release the cover you need to remove this pump. Turn the relief valve plug counterclockwise with a 27 mm socket to take it out, as well as the spring and the valve. Next unscrew the oil pump cover bolts and remove the oil pump cover and then remove the oil pump drive rotor and then the driven rotor. Wipe all parts with solvent and check for sign of wear or damage, the oiled relief valve should be able to move back and forth inside its bore. This valve has a sliding surface and a valve spring; both are changed as a set if worn out. Check the gap of the driven rotor-to-body, rotor side and tip by utilizing feller gauge and precision straight edge with corresponding replace worn parts or the new entire oil pump assembly. To remove the old crankshaft seal, pry it out from the timing chain cover and applying multi-purpose grease or engine oil on the outer part of the brand new crank seal to be installed and knock it into the cover using a deep socket and hammer, ensuring that the seal lip is also lubricated. Apply petroleum jelly with thin coat uniformly to the pump drive and driven rotors, place them in the timing chain cover where the marks are pointed out. Pour petroleum jelly into the pump cavity, put on the cover and, using a torque wrench, tighten the bolts to the required nominal torque. Grease the oil pressure relief valve with some clean engine oil and place it together with the spring in the pump cover and tighten the plug. Last, refit the timing chain cover, reverse through the steps of removal, fill with oil, put in a new filter, start the engine, and look for signs of leakage.

Remove the O-ring, oil pressure relief valve snap-ring, retainer, spring, and valve.