Intake and exhaust valves of OHV engine, except for 1.3 dm³ engine manufactured from September 1988
A - inlet;
E - graduation
An optimal valve timing clearance is necessary to compensate for thermal expansion when the engine warms up and reaches operating temperature. If the clearance is less than optimal, the valve timing changes, compression and engine power decrease, and the engine may not operate smoothly. If the valve clearances are increased, which is determined by the presence of characteristic knocks, the valve timing changes, the filling of the cylinders with fuel mixture and engine power decrease.
Checking and adjusting valve clearances must be done every 20,000 km of vehicle mileage.
Check and adjust valve clearances on a cold engine.
Valve clearances
| Valve | Optimal clearance, mm | Adjustment, mm |
| Inlet | 0,20 – 0,25 | 0,20 |
| Outlet | 0,56 – 0,61 | 0,60 |
Adjustment procedure
| The levers press on the stems of both valves in the cylinder | 1 | 3 | 4 | 2 |
| Adjusting the valve clearance in the cylinder | 4 | 2 | 1 | 3 |
1. Remove the air filter.
2. Remove the high-voltage wires from the spark plugs by the tips.
3. Remove the cylinder head cover, having first unscrewed the 4 bolts.
4. Turn the engine in the direction of its working rotation (clockwise) until the marks on the pulley and front cover are aligned. You can turn the engine crankshaft with a wrench on the pulley mounting bolt or by turning the wheel with the gear engaged.
5. Carefully turn the engine in one direction or the other until both valves in the first cylinder open, while the valves of the fourth cylinder are closed and there is a gap between the lever and the valve stem, which is measured with a feeler gauge and adjusted if necessary.
6. The adjustment is made by turning the adjusting bolt so that the feeler gauge, the thickness of which is equal to the size of the gap, moves with difficulty in the gap.
7. Turn the engine crankshaft 90° and check the clearance of the next valve. The clearances of the remaining valves are checked in the same way.
8. Install the cylinder head cover, air filter and connect the high-voltage wires.
The original can be found on this resource: FordBook.ru