Genuine Saturn LS Piston

Saturn LS Piston Parts Questions & Experts Answers

• Piston
  90571287
  Q: What steps must be taken before removing the piston and connecting rod assemblies on Saturn LS?

  A:

  Cylinder head removal and also oil pan must be also removed before one is able to pull piston and connecting rod assemblies. First, ensure that there is no ridge formation at the extreme limit in the travel of ring in each cylinder and that they are scrap off using a ridge reamer should they exist as these can lead to breakage of piston. After the ridges are removed, orient the engine with the Crankshaft vertical and measure the amount of endfloat of the connecting rod by inserted feeler blades into the cylinder bores; if it exceeds the limit, new connecting rods may be needed. Proceed as follows: locate and note the position of the connecting rods and their corresponding caps, loosen and remove the connecting rod cap bolts together with the cap which may cause the bearing insert to drop. Take out the connecting rod and piston assembly came out through the top of the engine, the same process is followed for all cylinders. Caps and inserts can be also reassembled to cover the bearing surface after the removal of the used parts. To start installment of new piston rings, the ring end gaps as well as the piston ring side clearance have to be checked. First the oil control ring has to be placed followed by the middle and the top ring with the correct positioning of all the three. Scrape the cylinder walls and debur the corners before placing the pistons/connecting rod and apply clean engine oil to the piston and rings. Insert piston ring compressor for piston to be fitted in to the cylinder, the connecting rod must fit on the crank shaft journal. Upon completion of instalment, use Plastigage to measure the oil clearance of the connecting rod bearing, make sure the bearing faces are wiped clean and lubricated before tightening the connecting rod cap with new bolts. The same must be done for all assemblies maintaining the cleanliness and correct orientation thorough out all the assemblies. Last, turn the crankshaft to look for binding and to set the connecting rod end play as required if you replaced any of the component.