2.2.22. Installation of piston rings

Before installation of new piston rings it is necessary to check gaps in piston rings. It is supposed that side gaps of piston rings were already measured and checked (watch the Section Check of a Condition of Pistons / Rods).


  1. Spread out pistons/rods assembled and new sets of rings so that they corresponded to the same pistons and cylinders with which their face gaps were measured and in which they will be established at assembly of the engine.
  1. Insert the top ring into the first cylinder and establish it perpendicular to a cylinder wall, having pushed it the piston bottom. The ring has to be in the lower part of the cylinder in lower ring engine points.
  1. For measurement of a face gap insert the probe which thickness is equal to gap width between its ends. The probe has to pass between the ends of a ring with an easy resistance. Compare result of measurement to requirements of the Size table and adjusting data at the end of the Management. If the gap is more or less, than it is required, then before working further, double-check whether correct are acquired rings.
  1. If the gap is too small, then it should be increased, otherwise the ends of a ring during the operation of the engine will meet together that can lead to serious damage of the engine. The gap can be increased, very carefully having filed it a small file. Clamp a file in a vice with elastic sponges, put on a ring a file so that the ends of a ring rested against its surfaces and for removal of material slowly move a ring. Carrying out this operation, move a ring only from the end of a file by the beginning.
  1. Too big gap is not critical if it does not exceed 1.0 mm. Again double-check whether correct are acquired rings.
  2. Repeat the procedure for each ring of the first cylinder and for each ring of other cylinders. Do not forget about compliance of rings, pistons and cylinders.
  3. When gaps between the ends of rings are carried out/are modified, rings can be installed on pistons.
  1. Usually establish the first an oil scraper ring (the lowermost on the piston). As a rule, it consists of three separate components. Establish a radial/axial dilator in a flute. If there is a uvula for rotation elimination, then be convinced that it is implanted into the opening drilled in a flute.
  1. Further establish the lower disk. At installation of disks of an oil scraper ring do not use the tool for installation of piston rings as they can be damaged. Instead arrange one end of a disk in a flute between a radial / axial dilator and a wall of a flute, strong hold it on the place and a ring lead round around the piston, filling a disk in a flute. Further in the same way establish the top disk.
  1. After installation of three components of an oil scraper ring check that the top and lower disks easily moved in a flute.
  2. Establish to the following an average ring. Usually the tag which has to be turned up, towards the piston bottom is applied on it.

Always follow the instructions printed on packing of rings or on a box - different producers can establish different requirements. Do not mix the top and lower rings as they have various cross sections.

  1. Make sure that the identification tag is turned towards the piston bottom, then establish a ring in an average flute of the piston (watch the drawing). It is not necessary to unclench a ring more, than it is necessary for putting on on the piston. Use the high-quality tool to installation of rings if it is available; that rings did not get to empty flutes it is possible to use old flat probes.
  2. In the same way establish the top ring. Make sure that the tag is turned up. Be attentive and do not mix the top and average rings.
  3. Repeat the procedure for other pistons and rings.