OEM Chevrolet Lumina Piston

Chevrolet Lumina Piston Parts Questions & Experts Answers

• Piston
  12564008
  Q: How to replace the piston, rod bearing in an engine on Chevrolet Lumina?

  A: The first step for replacing piston and connecting rod and bearing begins with removing the cylinder heads. Insert the Crankshaft into the bottom of piston travel then set a cloth above the piston while leveraging the cylinder bore ridge reamer (J24270) to eliminate the Piston Ring ridge. Rotate the Crankshaft until the piston reaches its uppermost point after which you should remove the material including the cloth and support the vehicle. You should now detach the Oil Pan and Oil Pump as well as removing the Crankshaft oil deflector. Set the Crankshaft at bottom dead center (BDC) position for the rod assembly service while applying matchmarks to connecting rod and caps. The removal of connecting rod nuts will open the path for connecting rod cap and lower connecting rod bearing extraction. Secure thread protectors onto the Crankshaft journal for prevention of damage. Follow up installation of the connecting rod bolt guide set (J5239) by pushing the piston and rod assembly through the cylinder before lowering the vehicle. Clean the engine block top with oil before removing its piston and connecting rod assembly and upper bearing components and connecting rod bearings for examination. Use honing followed by hot water detergent cleaning then dry it with a clean cloth before adding new engine oil for cylinder bore cleaning. Narrow down installation steps by applying new engine oil onto the piston rings and bearing surfaces and cylinder bore and piston. Then implement the j5239. Use the Piston Ring compressor (J8037) to stretch the rings before installation which should have their stamped arrows facing toward the front of the engine. The j5239 and j8037 should help install the piston in its bore by using a wooden hammer handle to tap lightly while keeping the j8037 against the engine block until all rings enter the cylinder bore. The technician should support the vehicle again while installing the upper connecting rod bearing and apply fresh engine oil before lowering the piston and rod assembly to the Crankshaft through the use of the j5239. The procedure requires you to first remove the j5239, insert the lower connecting rod bearing into the connecting rod cap which you should then coat with new engine oil before installation. To achieve a proper installation use the electronic torque angle meter (J36660-A) for an additional 75-degree rotation on the connecting rod nuts which should initially be tightened to 20 nm (15 ft. Lbs.). Check for binding in the connecting rod before measuring connecting rod clearance as you confirm all bearings are present along with light parallel rod tapping against the crankpin. As the final step install the Crankshaft oil deflector together with the Oil Pump and the Oil Pan before lowering the vehicle to install the Cylinder Head(s).