GM 19178305 Piston Kit,Engine

The piston and connecting rod assemblies can be removed only if the cylinder head and the oil pan are first detached. Palpate with your fingernail for any ridges at the upper limit of ring travel and be sure to use a ridge reamer to pare them down because, if not, your piston will surely break. Number each piston and draw an arrow toward the front of the engine, do not stamp or center punch. When the cylinder ridges have been milled off, turn the engine on its side so that the crankshaft is in the upward position and check the end-float of the connecting rod with feeler blanks as follows: Locate the connecting rods as well as the caps without any difficulties; reverse the cap bolts gradually to a thread-locking stage where the cap bolts can be easily unscrewed. Upon withdrawal of the connecting rod, unbolt the cap and the bearing insert gently and then release the connecting rod and piston together through the top of the engine but with assurance that all the ridge material has been eradiated. Do the same with the other cylinders and use the caps and inserts to save from being damaged. The pistons and connecting rods thus are suitable for inspection and reconditioning. These should be measured before one can proceed to put new piston rings on, the piston ring side clearance should also be properly done. Arrange the piston/connecting rod assemblies and purchase new rings on the basis of match for installation. Place the top ring, as it aligns with cylinder walls, install the first cylinder and check the end clearance with the feeler gauge. In the event the end gaps are too large, then filing of the ring ends should be done so as to optimize the gaps. First of the three rings to be fitted are the oil control rings with the contracted side fitting against the block. Cylinder wall should be clean and the edges should be chamfered before installation of the cylinder and crankshaft should be fitted. Take out all the old bearing inserts from the connecting rod and cap and install the new bearings without engaging in the process of lubrication, to ensure that new bearing insert fits properly. Align the piston ring gaps in 90-degree intervals, apply a coat of oil on the piston and the rings and use the piston ring compressor in placing the rings. Place the piston/connecting rod assembly into the cylinder with an eye on the presence of some level of resistance. After installation, confirm that the connecting rod bearing oil clearance has been done properly using Plastigage by ascertaining the sizes as well as condition of bearing inserts. Scrape off any Plastigage material, coat the bearing faces with a thin layer of grease or assembly lube, replace the rod cap with new fasteners and torque to the proper figure. The steps are to be repeated for rest of the assemblies making sure they are also clean and aligned correctly. Last of all, turn the crankshaft and check binding and the end float of the connecting rod and adjust it if any new parts put in.

Install the oil control ring first, followed by the middle and top rings, ensuring the correct orientation.

Check the ring end gaps and ensure the piston ring side clearance is correct.