Pistons and connecting rods — removal and disassembly

The details of the crank mechanism along with the pistons and connecting rods are shown in Figure 313. To remove the pistons and connecting rods, the cylinder head and oil pan must be removed (as well as an oil pump), however, the crankshaft can be left in the cylinder block. After this, the pistons and connecting rods are pushed upward using a hammer handle from the inside of the cylinder block, after the connecting rod bearing caps and bearing shells have been removed. Before carrying out this work, please read the instructions regarding markings, installation positions, etc., given for gasoline engines.



To separate the pistons from the connecting rods, the piston pin circlips must be removed. Then place the plunger in hot water (not less than 80°С) and knock it out using a suitable drift and hammer. Remove the piston rings using piston ring pliers. Checking the pistons and connecting rods is carried out in the same way as is done on gasoline engines, but taking into account the values given in the tables of sizes and adjustments. The connecting rod bearing shells are selected in accordance with the tolerance values. The bearing shells are marked with the numbers 1, 2 or 3 and the same number is stamped on the outside of the connecting rod bearing caps. Be sure to ensure that both markings match.