Setting the piston of the first cylinder to the TDC position of the compression stroke

The piston of the 1st cylinder is set to the top dead center position (TDC) compression stroke so that when carrying out work related to the removal of the camshaft drive belt, the installation of the valve timing is not disturbed. If the valve timing is disturbed, the engine will not work normally.

On the R4 16V Duratec Ti-VCT engine, the marks on the VCT mechanisms, made in conjunction with the camshaft pulleys, serve only for preliminary approximate installation of the crankshaft and camshafts in the required position. To accurately set the piston of the 1st cylinder to the TDC position of the compression stroke, two special devices are needed to fix the crankshaft and camshafts in a certain position.

You will need: special tools for fixing the crankshaft and camshafts, socket wrench «on 10», box wrenches or sockets «for 8», «at 13», key «at 18».

1. Remove the A/C compressor drive belt (cm. «Replacing the A/C Compressor Drive Belt») and accessory drive belt (cm. «Accessory drive belt replacement»).

2. Remove generator (cm. «Removal and installation of the generator»).



3. Remove the expansion tank from the brackets on the body and move it aside without disconnecting the hoses.


4. Securely support the engine.



5. Remove the right front power unit suspension support by unscrewing the two nuts securing it to the bracket on the engine and unscrewing the two bolts securing it to the engine compartment mudguard.



Pic. 4.13. Engine components removed when replacing the timing belt: 1 - crankshaft pulley; 2 - the lower cover of the timing belt drive; 3 - timing belt drive; 4 - front cover of the timing belt; 5 – arm of the right suspension support of the power unit; 6 - water pump pulley

6. Remove pulley 6 (see fig. 4.13) water pump by unscrewing the four bolts of its fastening.



Pic. 4.14. Fastening of an arm of the right support of a suspension bracket of the power unit


7. Remove bracket (see fig. 4.14) the right suspension support of the power unit by unscrewing the three bolts of its fastening.

8. Remove front cover 4 (see fig. 4.13) timing belt drive by unscrewing the eight bolts of its fastening.

9. Turn on the neutral gear in the gearbox.



Pic. 4.15. Alignment marks on VCT mechanisms

10. Turn the engine crankshaft by the bolt of its pulley so that the marks on the VCT mechanisms (valve timing changes) camshafts were installed, as shown in fig. 4.15 («at eleven o'clock»).



Pic. 4.16. Hole plug for installing the crankshaft fixing rod

11. Turn out the plug located in a forward part of the block of cylinders on the right (see fig. 4.16) and install the fixing rod into the opened hole until it stops against the crankshaft. Carefully turn the crankshaft by the bolt securing its pulley until the shaft stops with the fixing rod.

NOTE: The fixing rod is a cylindrical piece about 65 mm long (stepped in diameter). Part of a rod with a length of 10 mm of small diameter (4 mm) is a shank included in the groove of the crankshaft. The rest of the cylindrical part of a larger diameter (8 mm) serves as a guide in the bore of the cylinder block.

Pic. 4.17. Fixing the camshafts from turning with a special tool

12. Install the fixing device into the special slots in the VCT mechanism cases (see fig. 4.17). Install the tool so that the marks on its branches are at the top, with the line mark on the exhaust camshaft side and the dot mark on the intake shaft side. If the device was installed without difficulty, the timing belt is installed correctly, the piston of the 1st cylinder is at TDC of the compression stroke and the initial setting of the valve timing is correct. If the device cannot be installed (shifted valve timing), remove the timing belt, install the locking tool and put on the timing belt correctly (cm. «Replacing the timing belt»).

13. Install the removed parts in the reverse order of removal.