OEM 2004 Toyota Prius Timing Chain

2004 Toyota Prius Parts Questions & Experts Answers

• Q: How to replace the Timing Chain SUB-ASSY on 2004 Toyota Prius?

  A: The first step to replace CHAIN SUB-ASSY (1NZ-FXE) requires you to take off the oil pump assembly and the oil pump seal. Set the No. 1 cylinder to TDC/compression by first installing the washer to the crankshaft bolt and then adding the bolt to the crankshaft before rotating it clockwise to the specified position. The chain tensioner removal process starts with lifting the stopper plate followed by plunger unlocking then pushing the plunger to its extreme end and relocking it before inserting a 3.0 mm (0.118 inch) diameter bar into the stopper plate hole. The plunger needs unlocking followed by slight extension if you need to proceed with this step. First disconnect the chain tensioner by removing its two bolts then its tensioner slipper afterward unfasten the two chain vibration damper bolts to complete the chain removal. Install the chain tensioner only when timing marks are properly positioned while minimizing crude shaft rotation. The crankshaft needs to rotate counterclockwise by 40 degrees when the camshaft turns without the chain present. Secure the chain at the crankshaft timing sprocket with a string while keeping its timing mark aligned with the mark plate. Secure the chain vibration damper with two bolts measuring 9.0 Nm (92 kgf-cm, 80 inch lbs.). Afterward, take out the string then place the chain tensioner stopper. Install the chain tensioner through two bolts while torquing it to 9.0 Nm (92 kgf-cm, 80 inch lbs.) after performing the plunger unlock and lock procedure and inserting the 3.0 mm (0.118 inch) diameter bar. The chain tensioner installation requires removal of the 3.0 mm (0.118 inch) diameter bar and then the installation of an oil pump seal with Special Service Tool: 09950-60010 (09951-00250, 09951-00380, 09952-06010), 09950-70010 (09951-07100) followed by oil pump assembly installation.