Genuine 1986 Mercury Capri Piston

1986 Mercury Capri Piston Parts Questions & Experts Answers

• Q: What are the steps involved in preparing piston/connecting rod assemblies for inspection on 1986 Mercury Capri?

  A: It is only possible to start with the inspection process when all the piston/connecting rod assemblies had been washed, all original piston rings had been taken off the pistons, and new piston rings used in the re-assembly. Following the above steps, using a piston ring installation tool carefully take out the rings from the pistons without nicking or gouging it. Carefully remove all carbon deposits on the top of the piston using a handheld wire brush or fine emery cloth Always avoid using wire brush in a drill motor as this will cause serious erosion of the soft material of the piston. A piston ring groove cleaning tool should be used to scrape carbon off the ring grooves or a small piece of the old ring can be used with much care so as to avoid removing any metal or damaging the grooves. After elimination of the deposits, the piston/rod assemblies should be cleaned with the solvent and the subsequent drying with compressed air should be done looking at the oil return holes as well. Therefore, if the pistons and cylinder walls are in good condition or are not badly scored and the engine block is not rebored, new pistons may not be required; new piston rings, however, should always be fitted to an engine being rebuilt. A check for each piston must be looked for the crack, scoring, scuffing, holes, burned area as these are signs of overheating or abnormal combustion, thus cooling and lubrication system must be checked thoroughly. Small gullies point towards coolant leakage and this must be fixed so as to ensure that in the rebuilt engine, it does not reoccur. Check the piston ring side clearance with the feeler gauge at various positions of each of the grooves and fit the proper ring to each groove. The actual piston to bore clearance can be gotten by measuring the bore and piston diameter and ensuring they are matched while doing the arithmetic. If the clearance is more than permissible limits then rebore the block and have new pistons and rings fitted to it. The piston-rod clearance can be checked by rotating both piston and rod in one direction; a free move in classical sense of the word informs about excessive wear to be corrected by resizing and new pins at an automotive machinist. In case pistons can be chased out of the connecting rods, they should also be given to machine shop for checking for bend and twist. Last of all, check the connectingrod for crackage and damages For this gently turnover the rod caps and the old bearing inserts and clean the surfaces check them for any nicks or scratches before replacing the new bearings and finally tighten the rod caps. After a connecting rod knock, that will require a reconstruction of the engine, the rods should be replaced.