Attention! Breaking the toothed drive belt during operation can cause extensive engine damage. Replace the belt at the intervals specified in Specifications in Chapter Maintenance, or earlier if in doubt about his condition.
Note. F8Q 620 and early F8Q engines are fitted with a toothed drive belt "HTD", and later F8Q and all F9Q - a belt with a different tooth profile "HTD2". Whenever you replace a toothed drive belt, ALWAYS make sure you get the correct type of belt for the gears - the same goes for any gear that will be replaced.
Note. To check the tension of the toothed drive belt, you will need a special tool - see text. And to remove the crankshaft pulley - a suitable puller may be required.
When #1 piston is at TDC, the timing marks on the camshaft and fuel pump gears must be positioned as shown - F8Q 620 engine
A - Mark on the camshaft gear (aligned with pointer on outer drive belt cover - removed here)
B - Label on the gear wheel of the fuel pump - used with a Bosch pump
C - Slot for a segmented key
R - Fuel pump gear mark - used with Lucas pump
When piston #1 is at TDC, the timing marks on the camshaft and fuel pump gears must be positioned as shown - F8Q 784, F8Q 786 and F8Q 788 engines
A - Mark on the camshaft gear (aligned with pointer on outer drive belt cover - removed here)
B - Label on the gear wheel of the fuel pump - used with a Bosch pump
C - Slot for a segmented key
R - Fuel pump gear mark - used with Lucas pump
Removing
1. Disconnect the ground cable from the battery. On Scenic models, refer to Chapter Engine electrical equipment and disconnect the positive wire in the auxiliary power fuse box in the engine compartment, as well as the negative wire from the battery. After disconnecting the battery, unscrew the mounting bolt and move the additional unit to the side.
Attention! If the radio in your car is coded, make sure you know the code before disconnecting the battery.
2. Jack up the front right corner of the vehicle and remove the wheel and wheel arch liner (secured with plastic clips). Where available, remove the lower engine cover.
3. On models with F8Q engines, unscrew the mounting bolts and remove the upper plastic cover of the drive belt/right engine mount, marking the location of the holders attached with bolts. On models with F9Q engines, unscrew the fixing nuts and remove the soundproof engine cover, then disconnect the wiring connector from the injection control unit, unscrew the two fixing bolts and move the control unit to the side.
4. Remove the auxiliary drive belt. To improve access, unscrew the reinforcing rod (where available) between the domes of the front suspension struts.
5. Turn away a bolt of a pulley of a crankshaft.
6a. Remove the bolt.
6b. And a pulley from the end of the crankshaft (refer to illustrations).
7. To improve access, remove the two bolts securing the fuel filter assembly to the body panel, then release the filter hoses from the engine mountings. Assembly can be moved to the side (on top of the engine).
8. Temporarily install the crankshaft pulley bolt. Set piston No. 1 to TDC for also compression and insert the dowel pin to check the position of the crankshaft as described in Section Top dead center location (TDC) for piston No. 1.
9. Now you need to remove the right front engine mount so that you can remove the toothed drive belt; therefore, the engine under the sump must be supported by a jack with a block of wood laid between them to increase the area of support.
10. Remove the nut securing the top support bracket to the motion limiter/rubber pad assembly - refer to Section Replacing engine/transmission mounts.
11. Remove the three bolts securing the upper support bracket to the main bracket on the engine, then remove the bracket.
12. Turn away assembly of the limiter of the movement of a rubber pillow from a body. On F8Q engines with a turbocharger, also remove the rear support tie rod (Chapter Replacing engine/transmission mounts) and remove the bolts securing the muffler/converter downpipe to the exhaust manifold (contact the head Power and exhaust systems). Release the downpipe and support it.
13. Loosen the mounting bolts and remove the outer drive belt cover that covers the gear wheel of the high pressure fuel pump (refer to accompanying illustration).
14a. Loosen the mounting bolts, marking the location of the holders attached with bolts.
14b. Remove the cover that covers the camshaft gear (refer to illustrations).
15. Set piston No. 1 to TDC on the compression stroke and note the position of the alignment mark on the gear wheel of the high pressure fuel pump. On engines with fuel pump gear type "IAA", the alignment mark on the pulley may differ from that shown for the solid pulley. In this case, take into account the type of tag and its location in order to facilitate subsequent installation. Note that solid gear models have two alignment marks on the pulley. The label used depends on which fuel pump is installed (Bosch or Lucas) (refer to illustrations).
16. If the old belt will be used (contrary to Renault's recommendation), install it so that the arrows match the direction of rotation. Also note that the belt should have transverse strips that correspond to the alignment marks on the gears of the camshaft, high pressure fuel pump and crankshaft.
17. Loosen the mounting nut and bolt, then pull back the tensioner to reduce the belt tension (refer to accompanying illustration). Tighten the nut again.
18. Remove the belt first from the camshaft gear, then from the fuel pump gear, roller, crankshaft pulleys and intermediate shaft.
19. Do not turn the camshaft or crankshaft until the toothed drive belt is in place.
Note. Renault recommends replacing the timing belt every time it is removed. If the belt tension is checked using a special tool, then it will only be suitable for further use if the tension is within the limits specified in Specifications allowable deviations. If the tension is in the lower range of acceptable values, the belt cannot be tightened further, it must be replaced.
Inspection
1. Clean gears, idler and idler and wipe dry - do not use excessive solvent when cleaning idler and idler or bearing grease may be removed. Also clean the inner toothed belt cover and adjacent surface of the head and cylinder block.
2. Carefully inspect the toothed drive belt along its entire length, especially at the bases of the teeth. Replace the belt if it is contaminated with oil or grease. Replace any leaking seals. The belt must be replaced if the maximum mileage presented in Chapter Maintenance.
Installation
1. Make sure the No. 1 cylinder piston is at TDC and the dowel pin is inserted into the crankshaft. To be able to adjust the tensioner, screw a 6 mm bolt into the threaded hole in the inner cover of the toothed belt (refer to illustration).
2a. The arrows on the belt should point clockwise.
2b. Align the stripes on the belt with the marks on the crankshaft gears.
2c. Align the strips on the belt with the marks on the camshaft gears.
2d. Align the strips on the belt with the marks on the gears of the high pressure fuel pump, the direction of the arrows on the belt must match the direction of rotation of the engine. Install the toothed drive belt on the crankshaft gear, then on the idler pulley, injection pump gear, camshaft gear, tensioner and countershaft gear (refer to illustrations).
3. Make sure all alignment marks are aligned and remove any slack in the toothed drive belt by tightening the bolt on the inner cover.
Note. To check, count the number of teeth on the toothed drive belt between the intermediate mark on the fuel pump pulley - if the valve timing is correct, then there should be 29 teeth for F8Q engines, and 30 teeth for F9Q engines.
4. Now you need to adjust the belt tension, this can be done exactly with the tool Renault Mot.1273 (SEEM Tronic 105.6) (refer to accompanying illustration). If this equipment is not available, adjust the belt tension as far as possible using the method described below, and then contact a Renault workshop as soon as possible to check the tension. Do not go on a long trip or drive at high speed until the toothed drive belt tension has been checked.
5. If the adjustment is incorrect, the tensioner must be moved by loosening the nut and turning the bolt on the inner timing belt cover (refer to accompanying illustration).
6. Having properly tensioned the belt, tighten the tensioner nut to the torque given in the Specifications. Loosen the bolt on the inner timing belt cover so that it is no longer in contact with the tensioner pulley bracket.
7. Remove the crankshaft dowel pin, then install the crankshaft pulley and mounting bolt.
8. Make sure the crankshaft is set to TDC (to do this, insert the dowel pin), then remove the dowel pin and turn the crankshaft two full turns in the normal direction of rotation, returning it back to TDC. Re-insert the dowel pin into the cylinder block.
9. Temporarily install the outer drive belt cover that covers the camshaft sprocket and check that the alignment mark on the pulley is aligned with the pointer on the cover (refer to section Top dead center location (TDC) for piston No. 1).
10. Recheck the belt tension as described above. If the tension is incorrect, the installation and verification procedure must be repeated.
11. After tightening the belt, remove the M6 bolt from the inner cover and remove the dowel pin from the cylinder block. Install the plug in the cylinder block and securely tighten it and the tensioner mounting bolt.
12. Check the moment of injection as described in Chapter Power and exhaust systems.
13. Install the top outer drive belt covers.
14. Attach the motion limiter/engine rubber mount assembly to the body and to the engine top bracket as described in Section Removal and installation of an oil cooler. Remove the jack or other device that was used to support the engine.
15. Install the fuel filter assembly and secure the hoses. On F8Q engines with a turbocharger, install the rear support tie rod (Chapter Replacing engine/transmission mounts) and downpipe muffler/converter (contact the head Power and exhaust systems).
16. Install the auxiliary drive belt.
17. Where applicable, install reinforcing rod on front suspension domes.
18. On models with F8Q engines, install the drive belt/right support top plastic cover. On models with F9Q engines, install the injection control unit and wiring connector, then install the engine soundproof cover.
19. Where available, install the engine undershield, then the wheel arch liner and wheel, and then lower the vehicle to the ground.
20. Connect the ground cable to the battery, and on Scenic models, the terminals on the additional block.