Caution should be exercised during the removal process of the timing system, as any mistakes can lead to severe engine damage. It's advisable not to attempt this procedure without substantial experience in such repairs; consult an expert if uncertain. To initiate the removal, it's recommended to remove the engine/transaxle assembly and the drivebelt, including the drive-belt tensioner and idler pulleys. Set the engine to TDC and remove the crankshaft pulley with care to prevent any damage. Proceed to remove the timing chain cover bolts and the water inlet, along with its O-ring and gasket. Afterward, detach the timing chain cover, ensuring caution in specific removal spots to prevent cover damage. Remove the old crankshaft seal meticulously. Verify the No. 1 piston's position, setting it near TDC on its compression stroke. Ensure alignment of the timing marks on camshaft timing sprockets and the crankshaft sprocket. Following this, manipulate the No. 1 tensioner to lock it and remove it, subsequently removing the chain tensioner slipper. Proceed to remove the idler sprocket shaft and the chain vibration dampers. Take note of the timing marks on each sprocket before removing the No. 1 timing chain and the crankshaft timing chain sprocket. On the right (rear) cylinder head, compress chain tensioner No. 2 and insert a drill bit or punch to lock it. Remove the camshaft timing sprockets and chain assembly, ensuring components are kept separate. Repeat the process for timing chain No. 3 on the left (front) cylinder head. Inspect all timing chain assembly parts for wear or damage, checking the chains for stretch and sprockets for appropriate diameter. Measure idler sprocket oil clearance and evaluate the condition of tensioners and vibration dampers. Ensure correct operation of the chain tensioners. During installation, lock chain tensioner No. 2 with a drill or punch, then proceed to install the tensioners, followed by the timing chains on the camshaft sprockets. Align yellow marking links and timing marks as specified. Install chain guides, the crankshaft timing sprocket, and the idler sprocket collar. Verify alignment of timing marks on camshaft sprockets. Install the No. 1 timing chain, ensuring proper alignment of marks, and lock the No. 1 tensioner with a drill or punch. Remove the drill or punch and confirm tension. Clean surfaces, install a new crankshaft oil seal, O-ring, and apply RTV sealant on the timing chain cover. Slide the cover into place, reinstalling all bolts sequentially and ensuring proper torque. Finally, follow the reverse procedure for the remaining installation steps, refilling fluids, reconnecting the battery, and checking for leaks upon starting the engine.
Posted by LexusPartsNow Specialist 
