Engine disassembly will be described in detail further in the "Repair and Overhaul" section. This describes tasks that can be performed with the engine both removed and installed, eliminating the need to describe tasks related to specific disassemblies twice. If complete disassembly is required, individual work processes must be combined, and in the specified sequence.
In principle, when disassembling, all moving and movable parts should be marked before removal to ensure their installation in their original position. This is especially important for pistons, valves, bearing caps and bearing shells and applies to all engines. The parts must be folded to avoid confusion during installation.
Under no circumstances should bearing and sealing surfaces be marked with a drafting stamp or, even more so, with a digital stamp. Paint is best for marking parts. It is best to insert the valves into the bottom of an inverted cardboard box, and write their numbers on the box with poison. Figure 220 shows the placement of the valves in a cardboard box.
Figure 220. The valves can be inserted into the bottom of the inverted cardboard box in the order shown in which they are installed.
Many of the parts are made of aluminum and require handling accordingly. If hammering is required to separate certain parts, only a rubber, plastic or leather hammer should be used.
If there is no special mounting stand, appropriate wooden blocks should be cut to provide access to the top and bottom of the engine mounted on them. After removal, the cylinder head can be clamped in a vice with a metal clamp to which the intake manifold pin bolts are screwed.
Complete disassembly of the engine is carried out as follows.
- Drain the oil from the engine.
- Loosen the bolts connecting the gearbox to the engine and separate the gearbox from the engine, without placing the weight of the gearbox on the clutch shaft.
- Pull out the oil dipstick.
- Remove the leading and driven clutch discs. To lock the crankshaft when loosening the bolts, place the stopper shown in Figure 222 in the flywheel ring gear or hold the flywheel with a screwdriver inserted into the flywheel ring teeth.
Figure 221. The oil filter can be unscrewed with a chain wrench.
Figure 222. Holding the flywheel from turning. The locking segment should be inserted into the flywheel ring teeth.
- Remove the oil pan. To do this, place the engine on the cylinder block surface and evenly loosen the 23 bolts in a circle. Remove the oil pan (see Figure 223) and its gasket.
Figure 223. Removing the oil pan.
Figure 224. Parts removed from the front of the engine.
- Hold the flywheel from turning in the manner shown in Figure 222 and loosen the crankshaft belt pulley mounting bolts. The flywheel can also be removed at the same time. If necessary, tap it with a plastic hammer. The flywheel does not need to be marked, as it can only be installed in one position.
- After this, press the belt pulley off the crankshaft using two crowbars. You can also use a puller, the two bolts of which can be screwed into the threaded holes of the belt pulley.
- Unscrew both parts of the timing belt cover and remove it from the front of the engine. Use a screwdriver to pry up the spring clip used for fastening.
- Also remove the casing from the bottom side. Figure 225 shows the disassembly stage prior to this work operation.
Figure 225. Removing and installing the timing belt. 1. Inserted bolt; 2. Inserted bolt; 3. Inserted bolt; 4. Tensioner bolt; 5. Tensioner bolt; 6. Quadrangular hole
- Prepare three M8 x 40 bolts. Insert one of the bolts into place (1) in Figure 225, and the other two bolts into places (2) and (3) in the toothed pulley of the high-pressure fuel pump. In this case, the gas distribution mechanism is blocked. If complete disassembly of the engine is necessary, these works are not required. Bolts should only be inserted if valve timing adjustment is required.
- Loosen the bolts (4) and (5) of the timing belt tension roller. To compress the spring of the automatic tensioner, insert a ratchet extension with a 9.52 mm tetrahedron into the rectangular hole (6), as shown in Figure 226. This extension is included in the key head kit with a 3/8-inch adapter. Rotate the extension cable several times using the ratchet. To hold the spring in a compressed state, tighten the bolt (5) in Figure 225.
Figure 226. Removing the timing belt. Loosen the nut (2) and the nut closed by the ratchet mechanism in the figure, and then turn the timing belt tensioner with the extension (1) to compress the spring.
- Carefully remove the toothed belt from the sprockets.
- Remove the cylinder head as described in in the relevant section.
- Remove the five water pump bolts and remove the water pump assembly. There is a gasket located under the water pump.
- Unscrew the two bolts and remove the thermostat housing.
- Pull the timing belt sprocket off the crankshaft. This can be done using two crowbars.
- After unscrewing bolts (2) and (3) in Figure 227, remove the tension roller (4). A spring is installed on the inside of the mounting bracket. A special tool is used to hold the spring and pressure rod at the service station. Therefore, when lifting the mounting bracket, proceed with caution.
Figure 227. Remove the tension roller (4) after unscrewing bolts 1, 2 and 3.
- Unscrew the two bolts (1) in Figure 228 and remove the tension roller located in the middle.
Figure 228. Remove the tension roller located in the middle after unscrewing the bolts. 1. Bolts; 2. Tension roller; 3. Water pump
- Remove the cover installed in front of the oil pump (6 bolts) and remove the gasket. Carefully press the flange, which is seated on two pins.
- Unscrew the oil pump mounting bolt from the bottom of the engine (Figure 229), remove the drive chain from the oil pump sprocket. Figure 230 shows how to remove the oil pump while simultaneously disconnecting it from the drive chain.
Figure 229. Removing the oil pump. Pull out the spacer plate in the manner shown. The pump bolts are indicated by arrows.
Figure 230. Pull up on the oil pump sprocket while simultaneously removing the pump. After this, remove the drive chain and sprocket.
- Remove the oil pump drive sprocket and, after pulling out the crankshaft key, remove the chain.
- Remove the camshaft timing pulley and the high pressure fuel pump drive pulley. Figure 231 shows the parts to be removed.
Figure 231. Parts removed from the front of the engine.
- Remove the high pressure fuel pump and fuel injection pipes, using Figure 232.
Figure 232. Removing the high-pressure fuel pump and fuel injection pipes.
- Loosen the nuts securing the connecting rod bearing caps, remove the bearing caps and pistons together with the connecting rods and stack them in the order of installation.
- Having marked the relative positions of the main bearing caps and the crankcase, remove the caps. Place the lids and liners in the order they were installed.
- Remove the crankshaft oil seal from the flywheel side. The seal must be replaced.
- Remove the crankshaft and take the upper halves of the bearing shells out of the holes. Mark and also remove the half washers for adjusting the axial play of the crankshaft.
- Disassembly of pistons and connecting rods is carried out in accordance with the instructions relevant section. The piston pins are held in place by retaining rings in the piston pin bore grooves. Store parts in place.