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Advice

Mounting of the piston rings

The prerequisite for the correct operation of the new piston rings is their carefully made assembly on the piston. Your piston rings purchased from their manufacturer, the "Prima" SA Company in Lodz are perfectly adapted to the dimensions of the original pistons used in particular motors. One must observe the principle, that rings with a nominal dimension should be mounted to the piston of nominal diameter and oversize rings to oversized pistons with the same oversize, as the piston rings have. The piston rings should be fitted on new pistons, which guarantee the correct operation of the piston kit in the engine.

When installing the piston rings the special forceps should be used while taking care not to open live-mounted rings too wide, but only as far as it is necessary to pull them over on the piston. Remember, that excessive dilation can cause rupture or permanent deformation of the ring. A deformed ring will not provide a proper seal in the cylinder.

Particular attention should be paid to the mounting rings marked with "TOP" or "G" mark and put such rings in the grooves of the piston in such a way, that lateral surface of the ring marked with "TOP" or "G" was directed upwards, towards the piston crown. When the rings do not have the "TOP" or "G" on the piston assembly is free from this rule. Piston rings are mounted in the grooves of the piston in sequence starting from the bottommost one, i.e. the oil ring.

If the oil ring mounted on the piston is equipped with a helical spring, then you should at first take it out of the ring and insert into the adequategroove of the piston. Then with the special pliers open the ring and apply it onto the spring lying already in the groove of the piston. It should be noted that the junction of the spring  is  situated straigth in front of the piston ring joint. If the piston ring is located below the piston pin, the mounting of the piston rings should be started with this ring.

After installing all the rings, turn them into the grooves of the piston so that joints of the adjacent rings are transposed relative to each other.

Sectional steel oil rings (composed of three part) must be installed as follows:

a) Insert the spring into the groove of the piston. The joint of the spring should be located in a place, where the bottom of the groove is free from cracks or holes.

b) Hold the ends of the spring and install the top ring made of steel strip. Applying the upper steel ring, one should start  from its position being 45 ° -  90 °  left from the spring joint and insert it in the direction of the spring joint (with spiral movement).

c) Upon installation of the lower ring, made also of steel strip, one should start from its position being 45 ° -90 ° right from the spring joint and insert it in the direction of the spring joint (with spiral movement).

Finally, having completed the assembly, check if the ends of the spring joint are mutually supported and do not lie one on another.

After finishing the assembly, above-described, all the rings are clamped on the piston with a special steel band. Now introduce the piston into the cylinder with light taps. One  should be especially careful about  resting of the steel band around whole its circumference on the surface of the cylinder block, in particular so of the low axial rings do not pop out.