Engines E1, E3, E5, B3, B5, B6 up to 9/89, PN
To compensate for various thermal expansions, the timing mechanism must have a certain valve clearance.
If the gap is too small, the valve timing changes, compression becomes unsatisfactory, engine power decreases, the engine runs unstably. In extreme cases, valves or valve seats can be deformed.
If the gap is too large, a very strong mechanical noise appears, the valve timing changes, due to too short valve opening time, the engine does not develop maximum power, the engine runs unstably. Valve adjustment achieves the desired result only if the valves seal flawlessly, do not have unacceptable play in the guides and are not knocked off at the ends of the rods.
The valve clearance is checked and adjusted as part of maintenance, see Section Service technology, tools and equipment of the workplace, and after repair, or if there is noise in the timing mechanism. Valve clearance is checked and adjusted with the engine warm. The operating condition of the engine is achieved by driving 10-15 km under normal conditions, when the temperature gauge is in the middle region.
Gas engine
Examination
1. Remove the cylinder head cover.
2. Set the piston of the 1st cylinder to the TDC position, see Section Removal and installation of a gear belt of VZ, V5, B6 engines (SOHC), BP (SOHC).
3. To crank the crankshaft, engage 5th or 4th gear and move the vehicle on a level surface. Another possibility to turn the crankshaft: Raise the front wheel, shift into 5th or 4th gear and turn the wheel by hand.
4. Check whether the rocker arms related to the 1st cylinder have a small clearance on the valve, and the rocker arms of the 4th cylinder fit snugly. If this is not the case, the crankshaft should be rotated 1 more complete revolution.
![](https://www.mazbook.ru/img/familia/0528.jpg)
5. Check and, if necessary, adjust the clearance of the intake valve of the 1st cylinder (E1) and 2nd cylinder (E2), final 1st cylinder (A1) and 3rd cylinder (AZ) using a probe.
![](https://www.mazbook.ru/img/familia/0529.jpg)
6. Measure the clearance between the valve and rocker arm. See table for adjustment values.
7. The probe must be pulled through with effort, otherwise adjust the clearance.
8. Turn the crankshaft one turn (360°) continue until the mark on the belt pulley matches the mark on the drive belt cover.
9. Check and, if necessary, adjust the intake valve clearance of the 3rd cylinder (E3) and 4th cylinder (E4), as well as the final 2nd cylinder (A2) and 4th cylinder (A4).
10. The probe must pass with effort, otherwise adjust the clearance.
Adjustment
1. If the value is not correct, loosen the lock nut 1 turn with a wrench or box wrench. While doing this, hold the adjusting screw with a screwdriver.
2. Turn the adjusting screw with a screwdriver and adjust the valve clearance.
3. Then fix the adjusting screw with a lock nut.
4. Check the valve clearance again.
5. In the same way, check and adjust the clearance of all valves.
Attention! It is advisable to mark the rocker arms of already adjusted valves with chalk.
![](https://www.mazbook.ru/img/familia/0530.jpg)
6. Install the cylinder head cover.
Diesel engine
Examination
1. Remove the air filter, see chapter Power system, carburetor, fuel injection system, Chapter Removal and installation of the air filter.
2. Remove the cylinder head cover.
3. Set the piston of the 1st cylinder to the TDC position, see Chapter diesel engine.
4. To crank the crankshaft, engage 5th or 4th gear and move the vehicle on a level surface. Another possibility to crank the crankshaft is to lift the front wheel, shift into 5th or 4th gear and turn the wheel by hand.
5. Check whether the rocker arms related to the 1st cylinder have a small clearance on the valve, and the rocker arms of the 4th cylinder fit snugly. If this is not the case, the crankshaft should be rotated 1 more complete revolution.
![](https://www.mazbook.ru/img/familia/0531.jpg)
6. Check and, if necessary, adjust the clearance of the intake valve of the 1st cylinder (1) and 2nd cylinder (3), final 1st cylinder (2) and 3rd cylinder (6) using a probe.
![](https://www.mazbook.ru/img/familia/0532.jpg)
7. Measure the clearance between the valve and rocker arm. See table for adjustment values.
8. The probe must be pulled through with effort, otherwise adjust the gap.
9. Turn the crankshaft one turn (360) continue until the mark on the belt pulley matches the mark on the drive belt cover.
10. Check and, if necessary, adjust the intake valve clearance of the 3rd cylinder (5) and 4th cylinder (7), as well as the final 2nd cylinder (4) and 4th cylinder (8).
11. The probe must pass with effort, otherwise adjust the gap.
Adjustment
![](https://www.mazbook.ru/img/familia/0533.jpg)
1. If the value is not correct, loosen the lock nut 1 turn with a wrench or box wrench. While doing this, hold the adjusting screw with a screwdriver.
2. Turn the adjusting screw with a screwdriver and adjust the valve clearance.
3. Then fix the adjusting screw with a lock nut.
4. Check the valve clearance again.
5. In the same way, check and adjust the clearance of all valves.
Attention! It is advisable to mark the rocker arms of already adjusted valves with chalk.
![](https://www.mazbook.ru/img/familia/0534.jpg)
6. Apply silicone-based sealant to the marked areas (e.g. DOW CORNING Q 3-7057).
7. Install the valve cover and screw firmly 10 Nm.
8. Install the air filter, see chapter Power system, carburetor, fuel injection system, Chapter Removal and installation of the air filter.
Valve clearance
Engine designation | inlet | high school graduation |
E1, E3, E5 | 0.25 mm | 0.30 mm |
B3, B6 | 0.30 mm | 0.30 mm |
PN (diesel) | 0.20 mm | 0.30 mm |