3.5.3. Pistons and rods

Piston fingers fasten on both sides lock rings. In need of replacement of details remove only pistons from rods.

1. Pistons can be removed after removal of lock rings. Place the piston in hot water and beat out a finger, having put the piston on reliable laying, the corresponding core. One behind another remove rings.
2. When using other tool do not break a ring.

1. Carefully clear and check all details. At detection of damages or wear of details they should be replaced.

2. Measure gaps in pro-points of pistons. For check of a gap it is required that rings densely sat in pro-points. For check, using the drawing, apply a flat level to the piston to press rings in pro-points, and then at an angle insert probes to measure a gap. Before carrying out measurements of a pro-point it is necessary to clean carefully.
If gaps on height of piston rings are outside admissions, replace piston rings. At worst it is necessary to replace pistons. There are piston rings, and also pistons of the increased sizes.
3. Measure butt gaps of separate piston rings in openings of cylinders.
For this ring in turn insert into openings and push in an opening the turned piston before their installation in the lower part of an opening. Measure a butt gap, inserting probes from the lower party of a case of the engine.
4. At the results different from the values given in tables of adjustments and the sizes it is necessary to replace piston rings.
5. Check wear of piston fingers and their openings. The piston finger has to move in an opening in the piston with a tightness, when moving by his finger after good lubricant. Also the finger has to move in a plug opening on the diesel engine. At the same time the piston and a finger have to have room temperature. In a rod the finger sits on hard landing which thus cannot be checked. 
6. On the bottom of the piston is available the shooter, specifying in the direction of the movement of the car. Observance of adjusting situation is very important as the piston finger is implanted into the piston with shift. On pistons with the increased sizes the size of the piston is indicated its bottom (for example, "25", "50", etc.). Letters and figures on the bottom of the piston indicate engine type. The piston is marked by letters of CU.
7. Check lack of visible damages of rods. Surely replace the damaged rods. Before repeated installation it is necessary to check a distortion or a bend of rods on a workbench, especially, when pistons are removed. Surely replace the warped or curved rods.