Checking/adjusting valve clearance (Mazda Familia BG)

Contents: Engines E1, E3, E5, B3, B5, B6 up to…⇓ Gasoline engine ⇓ Diesel engine ⇓

Engines E1, E3, E5, B3, B5, B6 up to 9/89, PN

To compensate for various thermal expansions in the valve train, there must be a certain valve clearance.

If the clearance is too small, the valve timing changes, compression becomes unsatisfactory, engine power decreases, and the engine runs unstably. In extreme cases, valves or valve seats may become deformed.

If the gap is too large, a very strong mechanical noise appears, the valve timing changes, due to the valve opening time being too short, the engine does not develop maximum power, the engine runs unstably. Valve adjustment achieves the desired result only if the valves are perfectly sealed, do not have unacceptable play in the guides and are not knocked down at the ends of the rods.

The valve clearance is checked and adjusted as part of the maintenance, see Section Maintenance technology, tools and workplace equipment, and after repair, or if noise has appeared in the distribution mechanism. The valve clearance is checked and adjusted on a warm engine. The working condition of the engine is achieved by driving 10-15 km under normal conditions, when the temperature gauge is in the middle range.

Gasoline 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 the timing belt of engines B3, B5, B6 (SOHC), BP (SOHC).

3. To turn the crankshaft, engage 5th or 4th gear and move the car on a level surface. Another way to turn the crankshaft: Raise the front wheel, engage 5th or 4th gear and turn the wheel by hand.

4. Check if the rocker arms belonging to the 1st cylinder have a small gap on the valve, and if the rocker arms of the 4th cylinder fit tightly. If this is not the case, the crankshaft should be turned another full revolution.

5. Check and, if necessary, adjust the clearance of the intake valve of the 1st cylinder (E1) and 2nd cylinder (E2), the exhaust valve of the 1st cylinder (A1) and 3rd cylinder (A3) using a feeler gauge.

6. Measure the clearance between the valve and the rocker arm. See the table for adjustment values.

7. The feeler gauge should be pulled with force, otherwise adjust the gap.

8. Rotate the crankshaft one revolution (360°) further until the mark on the belt pulley aligns with the mark on the drive belt cover.

9. Check and, if necessary, adjust the clearance of the intake valve of the 3rd cylinder (E3) and 4th cylinder (E4), as well as the exhaust valve of the 2nd cylinder (A2) and 4th cylinder (A4).

10. The feeler gauge should pass with force, otherwise adjust the gap.

Adjustment

1. If the value does not correspond to the required one, loosen the lock nut with a regular or open-end wrench by 1 turn. At the same time, hold the adjusting screw with a screwdriver.

2. Turn the adjusting screw with a screwdriver and adjust the valve clearance.

3. Then secure the adjusting screw with the lock nut.

4. Check the valve clearance again.

5. Check and adjust the clearance of all valves in the same way.

Note: It is advisable to mark the rocker arms of the valves that have already been adjusted with chalk.

Note: It is advisable to mark the rocker arms of the valves that have already been adjusted with…

6. Install the cylinder head cover.

Diesel engine

Examination

1. Remove the air filter, see Chapter Power supply system, carburetor, fuel injection system, Chapter Removal and installation 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 turn the crankshaft, engage 5th or 4th gear and move the car on a level surface. Another way to turn the crankshaft: lift the front wheel, engage 5th or 4th gear and turn the wheel by hand.

5. Check if the rocker arms belonging to the 1st cylinder have a small gap on the valve, and the rocker arms of the 4th cylinder fit tightly. If this is not the case, the crankshaft should be turned another full revolution.

5. Check if the rocker arms belonging to the 1st cylinder have a small gap on the valve, and the…

6. Check and, if necessary, adjust the clearance of the intake valve of the 1st cylinder (1) and 2nd cylinder (3), the exhaust valve of the 1st cylinder (2) and 3rd cylinder (6) using a feeler gauge.

7. Measure the clearance between the valve and the rocker arm. See the table for adjustment values.

8. The feeler gauge should be pulled with force, otherwise adjust the gap.

9. Turn the crankshaft one revolution (360) further until the mark on the belt pulley coincides with the mark on the drive belt cover.

10. Check and, if necessary, adjust the clearance of the intake valve of the 3rd cylinder (5) and 4th cylinder (7), as well as the exhaust valve of the 2nd cylinder (4) and 4th cylinder (8).

11. The feeler gauge should pass with force, otherwise adjust the gap.