- Measure the piston ring height clearances in the piston grooves by sequentially inserting the rings into the corresponding groove on the piston, as described for gasoline engines. The gap is determined by a feeler gauge inserted into the gap between the ring surface and the piston groove surface. There are no official specified values, but it is believed that if the gap exceeds 0.10 mm, the piston must be replaced.
- After this, sequentially insert all piston rings from the top side into the cylinder bore. Using an inverted piston, push the ring down to a distance of 15 mm from the bottom edge of the hole. To do this, place the cylinder block on its side. To measure the joint gap, insert a feeler gauge into the ring joint. The joint clearances are not adjustable and if the joint clearances are increased, the piston rings must be replaced.
- Measure the piston diameter with a micrometer at a right angle to the piston pin along the lower edge of the piston jacket. Pistons are available in two size groups. Pistons and piston pins are supplied in pairs and are marked accordingly.
- To check the piston clearance, measure the bore diameter. The holes are measured in the longitudinal and transverse directions and at three levels along the height of the working cylinder liner. In this way the maximum and minimum diameter are determined. Record the results.
- After this, subtract the piston diameter value from the hole diameter values. The difference is the piston clearance value. If the clearance value is outside the range of 0.062 - 0.078 mm, new piston sets should be installed.
- Check the piston pins and piston bores for wear and damage. Pins are supplied complete with pistons only. The piston pin should move with suction in the piston bore (lubricated).
Original publication on the website [PEUGEOTBOOK]