Genuine 1999 Pontiac Grand Prix Crankshaft

1999 Pontiac Grand Prix Parts Questions & Experts Answers

• Q: Is crankshaft installation the first task in engine reassembly on 1999 Pontiac Grand Prix?

  A: Crankshaft installation is the first task in engine reassembly, assuming the engine block and crankshaft have been cleaned, inspected, and repaired. Position the engine with the bottom facing up, then remove the main bearing cap bolts and lift out the caps, laying them out in order for correct installation. If present, remove the original bearing inserts from the block and caps, wiping the bearing surfaces with a clean, lint-free cloth to ensure cleanliness. Clean the back sides of the new main bearing inserts and place one in each main bearing saddle in the block, ensuring that any grooved insert is installed correctly. Lay the corresponding bearing from each set in the main bearing cap, ensuring the tab fits into the recess and that the oil holes align. On specific engine models, install the thrust bearing in the designated cap and saddle. Clean the bearing faces and crankshaft main bearing journals, then lay the crankshaft in position. Check the main bearing oil clearance using Plastigage, placing it on each crankshaft main bearing journal and installing the caps in their original locations without disturbing the Plastigage. Tighten the main bearing cap bolts in three steps, starting from the center and working outward, then remove the caps to compare the width of the crushed Plastigage to the scale for clearance measurement. If the clearance is incorrect, verify that no dirt or oil interfered with the measurement before considering different bearing inserts. Carefully scrape off any Plastigage material from the journals and bearing faces. Lift the crankshaft out, clean the bearing faces in the block, and apply a thin layer of moly-base grease or engine assembly lube to each bearing surface, including the thrust faces. Lay the crankshaft back in place, clean the bearing faces in the caps, apply lubricant, and install the caps in their original locations. Tighten all bolts except the thrust bearing cap bolts to the specified torque, then tighten the thrust bearing cap bolts to 10-to-12 ft-lbs. Tap the ends of the crankshaft to align the thrust surfaces, retighten all main bearing cap bolts, and rotate the crankshaft by hand to check for binding. Finally, check the crankshaft endplay with feeler gauges or a dial indicator, ensuring it is correct if the thrust faces are not worn and new bearings are installed, followed by the installation of the new rear main oil seal.