Note: This action is not included in the maintenance schedule. This should be done if noise is heard from the valve timing mechanism, or if it is suspected that the loss of power has occurred due to incorrect valve clearances. A new valve cover gasket may be required during installation.
Examination
1. If necessary, release the hoses that pass over the valve cover from their mountings to improve access and move them to the side. If fuel lines are disconnected, plug the open ends to prevent dirt from entering.
2. On models with the F8Q engine, remove the mounting bolts and remove the upper plastic drive belt/right engine mount cover, noting the location of the mounting bolts. On models with the F9Q engine, unscrew the mounting nuts and remove the soundproof cover.
3. Unscrew the fastening nuts (f8Q engines) or bolts (f9Q engines) and remove the valve cover from the engine. Remove the gasket.
4. When performing the following procedure, the crankshaft should be turned with a wrench using the pulley bolt. To improve access to the bolt, jack up the front right corner of the car and remove the wheel and wheel arch liner (attached with plastic staples).
5. To make it easier to turn the crankshaft, remove the glow plugs (Section 5D) or fuel injectors (Section 4D).
6. Draw the location of the valves on paper, numbering them from 1 to 8 from the flywheel (i.e. 1E, 2I, 3E, 4I, 5I, 6E, 7I, 8E; where "E" is the exhaust valve and "I" is the intake valve) (see illustration).
4.6. Valve arrangement: A - Inlet valve; B - Exhaust valve.
7. Turn the crankshaft until the valves of cylinder No. 1 are in an intermediate position - i.e. the exhaust valve is closed and the intake valve is open. The piston of cylinder #4 will be at the top of the compression stroke, and both of its valves will be completely closed - and now you can check the clearances of both valves of cylinder #4.
8. Insert the feeler gauge of the correct thickness (see Specifications) between the working projection of the cam and the washer on the top of the pusher (see illustration).
4.8. Measuring valve clearance.
If the feeler gauge fits freely or does not fit at all, use feeler gauges of different thicknesses to determine the exact gap and record it so that you can later calculate the required thickness of the new washer. Please note that the intake and exhaust valve clearances are different (see Specifications).
9. After checking the valve clearances of cylinder #4, turn the crankshaft half a turn so that the valves of cylinder #3 are in an intermediate position, then check the valve clearances of cylinder #2. Also check the clearances of the remaining valves in the sequence shown (see illustration).
4.9. Valve clearance checking sequence.
Adjustment - F8Q engines
Note: A micrometer is required to perform the adjustment.
10. Where the valve clearance differs from the specified value, it is necessary to replace the adjusting washer, having first calculated the required thickness. The thickness is indicated on the underside of the washer, but it is better to measure it with a micrometer, as due to wear the washer may be thinner than indicated on it (see illustrations).
4.10a. The thickness is indicated on the back of the washer.
4.10b. Checking the washer thickness using a micrometer.
11. The required thickness of the washer is calculated as follows. If the measured gap is less than that specified in Specifications, subtract from the specified in Specifications gap measured gap, then subtract that difference from the thickness of the existing washer.
For example:
Calculation example - the gap is too small
Measured gap (A) = 0.15 mm
Required clearance (B) = 0.20 mm
Difference (B - A) = 0.05 mm
Thickness of installed washer = 3.70 mm
Required washer thickness = 3.70 - 0.05 = 3.65 mm
12. If the measured gap is greater than that specified in Specifications, subtract the gap indicated in the Specifications gap, and add the result to the thickness of the existing washer.
For example:
Calculation example - the gap is too big
Measured gap (A) = 0.50 mm
Desired clearance (B) = 0.40 mm
Difference (A - B) = 0.10 mm
Thickness of installed washer = 3.45 mm
Required washer thickness = 3.45 + 0.10 = 3.55 mm
13. The washer can be removed from the tappet without removing the camshaft if you have a special Renault tool (see illustration).
4.13 Renault Push Rod Tools - F8Q Engines. Position the notches (A) on the tappets perpendicular to the camshaft axis
14. To remove the washer, the tappet must be pressed against the pressure of the valve spring. In theory, this can be done by pressing the lever against the camshaft between the working surfaces of the cams with a suitable screwdriver, pressing the tappet with the adjusting washer down, but this is not recommended by the manufacturer. If you do use this method, be very careful not to damage the camshaft, cylinder head or tappet (see illustration).
4.14. Removing the tappet adjusting washer - F8Q engine.
15. When pressing the pusher, the working projections of the cams should be directed upward, and the pushers themselves should be turned so that their cuts are located perpendicular to the camshaft axis. Install the washer with the thickness marking facing down.
16. If the Renault tool is not available and a suitable replacement cannot be made, then to remove the washers it will be necessary to remove the camshaft as described in Chapter 8.
17. Remove the socket or wrench from the crankshaft pulley bolt.
18. Install the valve cover using a new gasket and tighten the mounting nuts to the torque specified in the Specifications.
19. Install the fuel injectors (as described in Section 4D), or glow plugs (Section 5D).
20. Install/connect any hoses that were displaced to gain access. If the fuel lines were disconnected, reconnect them and then bleed the fuel system as described in Section 4D.
21. Install the upper plastic drive belt/right engine mount cover.
Adjustment - F9Q engines
Note: A micrometer is required to perform the adjustment.
23. Where the valve clearance differs from the specified value, it is necessary to replace the adjusting washer, having first calculated the required thickness. The thickness is indicated on the underside of the washer, but it is better to measure it with a micrometer and then calculate the thickness of the new one as described for the F8Q engines in points 11 and 12 above.
24. The adjusting washers are seated in the tappets in such a way that they are very difficult to remove with the camshaft installed. To perform this procedure you will need a special Renault tool (see illustration), but first it will be necessary to remove the intake and exhaust manifolds and the turbo generator (see Section 4D).
4.24 Renault valve open tool - F9Q engines.
25. To remove the adjusting washer, turn the crankshaft in the normal direction of rotation until the adjustable valve is fully open. Insert the tool through the channel in the cylinder head so that the end of the tool is located on the valve seat (see illustration).
4.25. Installing the Renault valve locking tool - F9Q engines.
26. When removing the intake valve washer, rotate the crankshaft further 180° and reinstall the tool. The tool will lock the valve in the open position, providing enough clearance to remove the washer with a screwdriver. Use the same procedure for the exhaust valves, except that the crankshaft must be turned 180° against the normal direction of rotation.
27. Before installing the washer, wipe the top of the tappet and make sure all oil is removed from the washer recess at the top of the tappet. Install the washer into the pusher, the protrusion should be located in the recess of the pusher.
28. If you don't have a Renault tool, then to replace the washers you need to remove the camshaft as described in Chapter 8.
29. Remove the wrench from the crankshaft pulley bolt.
30. Install the valve cover using a new gasket and tighten the mounting bolts to the torque specified in the Specifications.
31. Install the fuel injectors (as described in Section 4D), or glow plugs (Section 5D).
32. Install the intake and exhaust manifolds and turbo generator as described in Section 4C.
33. Install/connect any hoses that were displaced to gain access. If the fuel lines were disconnected, reconnect them and then bleed the fuel system as described in Section 4D.
34. Install the engine soundproof cover.