Device 67.7824.9521 for checking chain wear (stretching)
1 – roller; 2 – adjusting nut; 3 – counterweight
Chain wear (stretch) check diagram
1 – rollers
Check and replace
1. Wash the chain in kerosene and then check the condition of its links.
2. There must be no chips, cracks or other damage on the rollers or cheeks.
3. When the engine is running, the chain stretches. It is considered to be operational if the tensioner provides its tension, i.e. if the chain has stretched no more than 4 mm.
4. Check the chain stretch using device 67.7824.9521 (see Fig. Device 67.7824.9521 for checking chain wear (stretching)), which has two stepped rollers 1, onto which the chain is placed. Using counterweight 3, the chain is stretched with a force of 294 N (30 kgf) or 147 N (15 kgf). Adjusting nut 2 ensures that the counterweight axis is parallel to the base of the device.
5. Stretch the chain with a force of 294 N (30 kgf), placing the counterweight in the extreme right position, then reduce the force by 147 N (15 kgf), moving the counterweight to the extreme left position. Repeat both operations once more and determine the chain stretch by the distance L (see Fig. Scheme of checking the wear (stretching) of the chain) between the axes of the rollers. By measuring the distance between the diameters d of the rollers with a caliper and adding the diameter d to it, you get the distance L between the axes of the rollers.
6. For a new chain, the distance L between the roller axes is 485.755+0,5-0,1 mm. If the chain has stretched to 490 mm, it should be replaced.
The information can be read on the website: VAZBOOK.ru
7. Before installing on the engine, lubricate the chain with engine oil.