Before the inspection process can be done, the piston/connecting rod assemblies need to be cleaned and the old piston rings need to be taken out of the pistons where in new piston rings are to be used during the reassembly of the engine. Now to prevent the damage of rings, put on there piston ring installation tool and gently slide off the rings from the pistons. Remove all carbon build up from the top of the piston by scraping it with a hand held wire brush or fine emery cloth gently so as not to scratch the piston which is normally made of soft material and should not be scraped using wire brush that is mounted on a drill motor. Clean the ring grooves with a piston ring groove cleaning tool or a piece broken off the cylinder head old ring in a manner that it takes all the carbon without scrapping the grooves. After having dismantled the deposits, wash the piston/rod assemblies with solvents and dried using compressed air; the orifices should be clear for the oil return. If the pistons and cylinder walls are not too bad and the block is not rebored new pistons are not always required although new piston rings must always be fitted at a rebuild. Scan each piston for crack, scoring scuffing hole and burned areas since these are telltale signs of overheating or abnormal combustion and therefore calls for examination of cooling and lubrication system. Small barely visible pits are indications that there is leakage in the coolant and this has to be repaired. Check and measure the piston ring side clearance and pistons to bore and pistons to rods must be within standard limits while worn out areas shall be fixed. If pistons require one to be liberated from connecting rods, then these should be delivered to an automotive machine shop for evaluation. Clean and inspect connecting rods for any signs of wear and degenerate bearings replacing old ones if necessary. When replacing the piston rings ensure that the flow of ring ends is accurate, compatible with the piston and cylinder. Place the top ring within the first cylinder, align it to the cylinder walls and then check the end play with feeler gauges and adjust to the factory specification if required. Do this for each ring and cylinder until the oil control ring components and the middle and top rings are properly installed and after the correct order of installation has been given by the manufacturer to prevent confusion.
