Size groups of pistons and cylinders for the ZMZ-4062 engine

All parts of the connecting rod and piston group are divided into categories and individually matched to each other

Tables of size groups of pistons, block cylinders, pins and connecting rods, as well as mate sizes in the tables at the bottom of the article

The designation "406" on the piston indicates that it is intended for the ZMZ-4062 engine.

Two designations are embossed on the piston crown. According to the letter applied with paint, on the new block, the piston approaches the cylinder.

When repairing with cylinder boring, the required clearances are provided in the process of boring and honing for pre-purchased pistons of repair size.

Roman numeral indicates required finger group.

The diameters of the holes in the piston bosses, the connecting rod head and the outer diameters of the piston pin are divided into four groups marked with paint: I - white, II - green, III - yellow, IV - red.

On the fingers, the group number is indicated by paint on the inner surface or ends. It must match the group indicated on the piston.

On the connecting rod, the group number is also indicated by paint. It must either match or be adjacent to the group finger.

The finger lubricated with engine oil should move with little effort in the connecting rod head, but not fall out of it.

Heat the piston to a temperature of 60-80°C. We insert the connecting rod head between the piston bosses and press in the lubricated piston pin.

If there is no fixture, you can press the finger with a copper or ordinary hammer, through a soft metal mandrel, holding the piston in the air.

After assembly, the tab on the bottom end of the connecting rod should be on the same side as the "FRONT" lettering on the piston.

We fix the piston pin on both sides with retaining rings.

Checking the piston rings. The compression rings installed in the cylinder to a depth of 20-30 mm should have a gap in the lock - 0.3-0.6 mm, oil scraper - 0.5-1 mm.

We put the rings on the piston.

Spreading the lock of the oil scraper ring expander, we put it on the piston in the lower groove, and reduce the lock.

We put an oil scraper ring on the expander. The angle between the locks of the ring and expander with a one-piece ring is 45°, split - 90°.

We put on the lower compression ring with the inscription “TOP” to the piston bottom.

Last put on the top compression ring.

Pistons, pistons and connecting rods