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 95 a. Timing chain tensioner mechanism: 1 - cork; 2 - plug gasket; 3 - ball; 4 — spring seat; 5 - pressure spring; 6 - finger; 7 - relief valve; 8 - sealing ring; 9 - ball; 10 - pressure spring; 11 — push rod; 12 — retaining ring; 13 — bolt securing the sprocket to the camshaft; 14 — washer of the bolt securing the sprocket to the camshaft; 15 — bolt securing the sprocket to the camshaft; 16 - chain lock; 17 - chain tensioning shoe; 18 - shoe support finger; 19 — sealing gasket of the chain tensioner on the cylinder head; 20 — chain tensioner
The position of the drive chain tension shoe is shown in the figure 95a and 96. To replace the drive chain tension shoe, it is necessary to remove the cylinder head and the camshaft drive mechanism cover. The synthetic coating of the shoe cannot be replaced, so the shoe assembly must be replaced when the coating wears out. The process of replacing the chain tensioner shoe must be carried out as follows:
- remove all parts that create an obstacle to free access to the front of the engine. The battery must be disconnected;
- remove the cylinder head (see subsection 2.4.1);
- remove the camshaft drive mechanism cover (see subsection 2.5);
- use paint to mark the crankshaft sprocket and drive chain;
Figure 99. Marks on the camshaft drive sprocket and drive chain
- apply marks to the camshaft sprocket and drive chain (figure 99);
Figure 100. Fixing the camshaft drive sprocket
- unscrew the camshaft drive sprocket mounting bolt, having first secured it from turning. You can fix and hold the sprockets from turning using a mandrel (figure 100);
- remove the camshaft drive sprocket;
- tilt the tension shoe inward and remove it from the support pin;
- check the degree of wear or damage to the synthetic surface and replace the shoe if necessary;
- install the shoe in the reverse order of removal. Tighten the camshaft drive sprocket mounting bolt. Tighten the bolt to a torque of 25 Nm, and then tighten it another 85–95° while simultaneously holding the camshaft from turning. When installing the drive chain, make sure that the paint marks on the drive chain and both sprockets are aligned.
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