Figure 44. Camshaft drive mechanism cover with individual parts indicated (the details of the lid are shown below): 1 — support pin of the generator drive belt tensioning mechanism; 2 - oil dipstick guide tube; 3 — TDC position indicator pin; 4 - hole with flange for vacuum pump; 5 — TDC sensor mounting pin on four-cylinder engines; 6 — front crankshaft oil seal; 7 — bolt for fastening the camshaft drive mechanism cover to the cylinder block; 8 — TDC position indicator pin; 9 — seat bushing for mounting the TDC sensor; 10 — front crankshaft oil seal; 11 — bolt for fastening the camshaft drive mechanism cover to the cylinder block; 12 - elastic Grover washer; 13 — location of installation of the front crankshaft seal; 14 — camshaft drive mechanism cover; 15 — seat bushing of the power steering pump
The front crankshaft oil seal in the camshaft drive mechanism cover can be replaced on the engine installed in the vehicle if oil leaks are detected. First, you should make sure that the oil is leaking through the front crankshaft seal, and not at the sealing point of the camshaft drive mechanism cover. If the leaks are caused by a leak in the lid, it should be resealed (see subsection 2.4 and the right part of the drawing 44).
The front crankshaft oil seal must be replaced as follows:
- remove the belt pulley, vibration damper and hub following the instructions described in subsection 2.9;
Figure 94. Removing the front crankshaft oil seal
- using a screwdriver, remove the seal from the camshaft drive mechanism cover. In this case, you should place a piece of thick cloth under the screwdriver to avoid accidentally damaging the cover or crankshaft (figure 94);
- clean all parts thoroughly, remove burrs from the edges of the hole in the camshaft drive mechanism cover if necessary;
- if necessary, remove the cuff from the cover using a screwdriver. You have to be very careful not to damage the lid;
- carefully clean the sealing surfaces on the cylinder block and the camshaft drive mechanism cover;
- install a new crankshaft oil seal into the cover if the old one has been removed and needs to be replaced. The sealing lip of the new ring is offset by 3mm, so it will not sit on the crankshaft flange at the same point as the old ring. The space between the sealing lip and the dust-catching lip should be filled with approximately 1 g of plastic grease;
- apply sealant to the sealing surface of the cover and attach it to the cylinder block so that the mounting pins fit into the holes provided for them. Tap the lid gently from above to make it fit more tightly. At the Mercedes-Benz service station, a special clamping tool is used for these purposes;
- first tighten the two lower bolts, and then all the others with a torque of 10 Nm;
- then carry out the work in the reverse order of removal.