- remove all components and parts that impede access to the end of the engine;
Figure 96. Camshaft drive mechanism assembly: 1 - crankshaft sprocket; 2 - chain tension shoe; 3 - chain tensioner; 4 — camshaft drive sprocket; 5 - chain tensioner; 6 — fuel pump drive sprocket; 7 - chain tensioner; 8 — oil pump drive chain tensioner lever; 9 — oil pump drive sprocket
Figure 105. Removing the tension lever
- remove the tension lever mount with the oil pump drive chain pressure shoe as described in previous subsection, and remove the lever 8 shown in the figure 96 (see also figure 105);
- unscrew the bolt securing the oil pump drive sprocket and remove the sprocket from the shaft, while simultaneously removing the drive chain from the crankshaft sprocket;
- the position of the camshaft drive sprockets and the oil pump drive sprocket must be marked on the crankshaft in a corresponding manner so that they can be returned to their original position during subsequent assembly;
Figure 99. Marks on the camshaft drive sprocket and drive chain
- apply paint marks to the camshaft sprocket and camshaft drive chain as shown in the figure 99;
- remove the sprocket from the camshaft, thereby releasing the tension on the drive chain;
- remove the sprocket from the crankshaft using a suitable puller;
- check the condition of the crankshaft keys (sprocket and pulley keys), if there are signs of wear, replace them with new ones;
- if it becomes necessary to replace the crankshaft sprocket, you need to copy the mark from the old sprocket onto the new one, marking the corresponding tooth with paint relative to its keyway.
The installation of the sprocket on the crankshaft must be carried out in the following order:
- insert new keys into the special crankshaft sockets. Both surfaces must be parallel to the crankshaft axis;
- using a suitable mandrel, press the sprocket onto the crankshaft flange. Check the correct fit of the key;
- install the sprocket and camshaft drive chain. Please note the markings made with paint before dismantling;
- turn the engine over several times, paying attention to the marks on the top side of the camshaft (see figure 99);
Figure 107. Installing the sprocket on the oil pump shaft
- install the oil pump sprocket back into place. The hub of the oil pump sprocket has special seating edges that match the hole on the oil pump shaft, as shown in the figure 107;
Figure 106. Correct position of the oil pump drive chain tensioner lever with pressure shoe
- install tension arm with pressure shoe for oil pump drive chain (see figure 106);
- install the camshaft drive mechanism cover in its place (subsection 2.5);
- perform installation in the reverse order of removal.