Gas distribution mechanism drive (VW Passat B5)

Timing drive mechanism

1 - camshaft sprocket;
2 - pulse rotor for Hall sensor;
3 - camshaft sprocket mounting bolt, 10 Nm. Before screwing in the bolt, lubricate the lower surface of the bolt head with a thin layer of engine oil. When tightening the bolt, hold the camshaft from turning with a 24 mm wrench;
4 - pivot pin, 18 Nm;
5 - O-ring. If damaged, use a new O-ring;
6 - chain tensioner, 40 Nm;
7 - shoe;
8 - asterisk;
9 - Double-row roller chain. Before removing the chain, mark the direction of rotation of the chain;
10 - bolt, 100 Nm;
11 - asterisk;
12 - bolt, 10 Nm;
13 - Chain tensioner. Before removing the chain tensioner, use a screwdriver to release the locking gear and separate the chain guide from the tensioner. The engine can only be turned with the chain tensioner installed;
14 - leading chain sprocket,
15 - single chain;
16 - chain guide;
17 - special pin for chain guide, 10 Nm;
18 - guide pin with flange, 10 Nm;
19 - bolt, which is installed using a special tool VW-D6, 20 Nm,
20 - bolt, 20 Nm;
21 - chain guide;
22 - bolt installed using a special tool VW6, 20 Nm;
23 - guide ring;
24 - intermediate shaft

Places to apply marks before removing the timing chains

The location of the groove on the intermediate shaft sprocket when the piston of the first cylinder is set to TDC in the compression stroke

The arrangement of the elements of the gas distribution mechanism when the piston of the first cylinder is installed at the top dead center in the compression stroke

1 - chain:
2 - chain guide;
3 - front sprocket of the intermediate shaft;
4 - rear sprocket of the intermediate shaft;
A - chain tensioner mechanism lock;
B - the installation tooth on the crankshaft sprocket must be in line with the connector of the main bearing cap No.1;
C - timing mark on the intermediate shaft sprocket;
D - timing mark on the intermediate shaft sprocket

The camshafts are driven from the crankshaft, not directly, but through an intermediate sprocket. A smaller diameter sprocket is fixed on the same shaft as the intermediate sprocket, through which the second chain is driven by the valve timing mechanism. The upper chain of the camshaft drive is tensioned by a plate tensioner, which is held in the required position by an externally located adjusting bolt. The lower chain of the valve timing mechanism drive has a hydraulic tensioner, which does not require adjustment.

Execution order

1. Before removing the timing chains, use paint to mark the chains in the locations shown in Fig. Locations for marking before removing the timing chains.

2. Rotate the engine crankshaft to a position where the piston of the first cylinder is at top dead center. In this case, the timing mark on the crankshaft pulley/vibration damper should be aligned with the pointer on the chain cover.

3. When the piston of the first cylinder is set to TDC, a groove should be visible on the sprockets of the intermediate shaft (see fig. Location of the groove on the intermediate shaft sprocket when the piston of the first cylinder is set to TDC in the compression stroke).

If the groove on the intermediate shaft sprocket is not visible, rotate the engine crankshaft one full revolution and re-align the timing marks with the pointers.