БЛОК ДВИГАТЕЛЯ ДЕТАЛЬНОЕ ОПИСАНИЕ

Cylinder Head Sub-assembly

1. A cylinder head made of aluminum alloy (AlSi7MgCu0.5) is used.

2. A camshaft housing sub-assembly is located in the cylinder head sub-assembly. The camshafts are supported in their own camshaft housing sub-assembly. The camshaft housing sub-assembly is made from the aluminum-silicon alloy (AlSi9Cu3(Fe)).

   

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   *1	Cylinder Head	*2	No. 2 Camshaft (Exhaust Camshaft)
   *3	Camshaft Housing Sub-assembly	*4	Valve Rocker Arm Sub-assembly
   *5	Valve Lash Adjuster Assembly	*6	Valve Spring
   *7	Valve Guide Bushing	*8	Exhaust Valve
   *9	Intake Valve	*10	Glow Plug Assembly
   *11	Camshaft (Intake Camshaft)	-	-
   *a	Cross-section	*b	Exhaust Port
   *c	Intake Port	-	-

3. This engine has 4 valves per cylinder. By using a 4-valve cylinder head, the injector can be positioned in the center of the cylinder. As a result, high output and low exhaust emissions have been achieved.

4. This engine forms a flat combustion chamber roof. The intake and exhaust valves are arranged parallel to each other.

5. A distinction is made between the intake ports of the swirl port and tangential port, which provides for optimum mixture preparation and cylinder charge. The swirl and tangential ports are already separated in the intake manifold and are routed separately from each other in the cylinder head. The exhaust ports for each cylinder are already joined in the cylinder head so that only one exhaust port feeds into the exhaust manifold. The swirl port generates a swirl in the cylinder and the tangential port maintains the optimal cylinder charge.

   

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   *1	Exhaust Valve	*2	Intake Valve
   *3	Glow Plug Assembly	*4	Injector Assembly
   *a	Exhaust Port	*b	Tangential Port
   *c	Swirl Port	-	-

6. This engine uses a cylinder head with cross-flow cooling, where the coolant flows from the hot exhaust side to the cool intake side. This has the advantage of providing uniform heat distribution in the overall cylinder head. It also prevents additional pressure losses in the cooling circuit.

Cylinder Head Gasket

1. A 3-layer metal-layer gasket is used.

2. The 2 spring steel layers (function layers) of the cylinder head gasket are made from a spring band. The stopper is impressed onto the intermediate layer (spacer layer). The spring steel layers are made from stainless steel. Additional partial coatings optimize the function of the cylinder head gasket.

3. Metal-layer gaskets made of multi-layer sheet steel inserts are used in engines which are subjected to high loads. The primary characteristic of the metal-layer gasket is that the seal is determined by the integrated bead and stopper layers in the sheet steel inserts.

4. The deformation properties of the metallic cylinder head gasket enable the gasket to adapt optimally to the components in the cylinder head area while providing for a high degree of elastic recovery to compensate for component deformation. Such elastic recovery arises in response to thermal and mechanical loads.

5. The cylinder head gasket comes in 3 different thicknesses, depending on the respective piston protrusion. The thickness is identified in the cylinder head gasket by holes, where one hole signifies the thinnest and three holes signify the thickest.

   Gasket Thickness

   Bore Holes	1	2	3
   Gasket Thickness	0.95 mm (0.0374 in.)	1.05 mm (0.0413 in.)	1.15 mm (0.0453 in.)

   

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   *1	Cylinder Head Gasket	-	-
   *a	Identification of cylinder head gasket thickness	*b	Outer Spring Steel Layer
   *c	Intermediate Layer with Impressed Stopper	-	-

   Tech Tips

   For details of the installation of the cylinder head gasket, refer to the Repair Manual.

Cylinder Block Sub-assembly

1. A cylinder block made of heat-treated aluminum alloy (AlSi9Cu3) is used.

2. This engine has cylinder liners. The gray cast iron liners are cast during the manufacture of the cylinder block. Dry liners are used that do not have any direct contact with the coolant. The coolant jacket is completely enclosed by the cylinder block sub-assembly casting.

3. The structure of the cylinder block is divided into different areas:

   
   

   • Deck

   • Bearing seat area (bearing seat and bearing cap)

   • Cylinder

   

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   *1	Cylinder Block	*2	Cylinder Liner
   *3	Crankshaft Bearing Cap	-	-
   *a	Cross-section	*b	Oil Passage
   *c	Ventilation Window (Opening)	*d	Bearing Seat
   *e	Bore Hole for Crankshaft	-	-

4. This engine is equipped with a closed-deck design cylinder block. In the case of the closed-deck design the cylinder block deck is to a large extent closed in the area around the cylinders. Openings are created in the form of bore holes and ducts for pressure oil, oil return, engine coolant, cylinder block sub-assembly ventilation and cylinder head bolts.

   Tech Tips

   The difference between a closed-deck design cylinder block and open-deck design is shown in the illustration.

   

   Text in Illustration

   *a

   Closed-deck Design

   *b

   Open-deck Design

5. The bearing seat area (bearing seat and bearing cap) absorbs the force applied to the crankshaft bearing.

6. The bearing seat is the upper half of a crankshaft bearing in the cylinder block sub-assembly. Bearing seats are always integrated in the cylinder block sub-assembly casting. This engine features ventilation windows in the bearing seats above the crankshaft. When the engine is running, the gas is continually kept moving in the crank space. The movements of the pistons act like pumps on the gas. The ventilation windows reduce pumping losses, since pressure compensation in the entire cylinder block sub-assembly is made easier.

7. The crankshaft bearing caps form the lower seal with the bearing seats and are bolted to the seats. During the processing of manufacturing the cylinder block sub-assembly bearing seat and crankshaft bearing cap are jointly machined. It is therefore absolutely essential to locate them in position in relation to each other.

8. This engine makes use of a relative new way of providing exact positioning. This involves an impression in the contact surface between the bearing seat and the crankshaft bearing cap. This method of location ensures that an absolutely smooth transition surface is maintained, even after renewed assembly, in the bore hole for the crankshaft bearing between the bearing seat and the crankshaft bearing cap. When the impression connection is made the crankshaft bearing cap is designed with a profile. When the crankshaft bearing bolts are tightened for the first time, this profile is impressed into the cylinder block sub-assembly-side bearing seat surface and facilitates positive locking in the engine transversal and longitudinal directions.

9. To ensure positive locking in the engine longitudinal direction, the profile must be shorter than the cylinder block sub-assembly-side contact surface. Thus the profile does not protrude, but instead has a stop. In order not to make the bearing seat wider than is necessary, the crankshaft bearing cap is slightly constricted in the area of the profile. 2 profile elements per contact surface are used. The crankshaft bearing cap is made from very strong sintered iron.

   

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   *1	Crankshaft Bearing Cap	-	-
   *a	Bearing Seat	-	-

Oil Pan Sub-assembly

1. An oil pan sub-assembly made of die-cast aluminum is used.

2. A special feature of the oil pan sub-assembly is the connection of the stabilizer link, which supports the engine torque. The mass application of force is effected by four M10 bolt connections. The power flow to the cylinder block is provided by reinforcing ribs on the outside and inside of the oil pan sub-assembly.

   

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   *a

   Reinforcing Rib

   *b

   Stabilizer Link (Bolting Point)

Crankshaft and Crankshaft Bearing

1. A crankshaft made of forged steel is used.

2. The crankshaft has 4 balance weights and 5 bearing journals.

   

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   *1	Crankshaft	*2	Balance Weight
   *3	Bearing Journal	-	-
   	Transaxle Side	-	-

3. The crankshaft bearings subjected to high loads are designed as tri-metal bearings. The steel backing, the lead-free bronze and the bearing metal layer made from a tin-copper alloy provide the basis for wear-resistant bearings with high load capacities.

   

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   *1	Crankshaft Bearing	-	-
   *a	Steel Backing	*b	Aluminum Bronze
   *c	Bearing Metal Layer	-	-

4. There are 2 oil holes in the upper crankshaft bearing. This is because the oil hole in the bearing seat is located alternately on the left or right side, whereas the bearing shell should be a common part.

5. An all-round groove in the upper crankshaft bearing improves the distribution of the oil. This groove however reduces the size of the sliding surface and thereby increases the effective pressure. Strictly speaking, the bearing is split into 2 halves, each with a smaller bearing capacity. The oil grooves are therefore only situated in the zone not subjected to load. The bearing is also cooled by the engine oil.

6. The crankshaft has only one thrust bearing. This bearing holds the crankshaft in the axial direction and absorbs forces in the longitudinal direction. A built-up thrust bearing is used in this engine.

7. Built-up bearings are made up of several separate components. Thrust washers are fitted on both sides to provide for a stable, loose connection with the crankshaft bearing and facilitate easy installation. The thrust washers are movable, thereby making contact more uniform and reducing wear. Also, 2 built-up bearing halves are installed to guide the crankshaft. These provide the crankshaft with a 360° thrust bearing and very good stability against axial displacement.

8. The thrust bearing is located in the middle of the crankshaft at the position of the No. 3 crankshaft bearing. This allows thermal expansion to occur more uniformly. The steel of the crankshaft and the aluminum of the cylinder block sub-assembly have different coefficients of thermal expansion, i.e. in the case of temperature differences the level of thermal expansion also differs. If the thrust bearing were located at one of the ends of the crankshaft, the expansion difference in relation to the cylinder block sub-assembly over the length of the entire crankshaft would be very great. However, because the thrust bearing is located in the middle, thermal expansion is distributed symmetrically in both directions. This means that the expansion difference at the 2 ends of the crankshaft is only half as great.

   

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   *1	Upper Crankshaft Bearings (in Bearing Seat)	*2	Lower Crankshaft Bearings (in Bearing Cap)
   *3	No. 3 Upper Crankshaft Bearing	*4	No. 3 Lower Crankshaft Bearing
   *5	Thrust Bearing	-	-
   *a	Oil Groove	*b	Oil Hole

   Tech Tips

   
   

   • It is extremely important to handle the crankshaft bearings with care, as the very thin bearing metal layer can be easily damaged.

   • It is important to ensure that the bearing is lubricated with engine oil. Overheating is usually the cause, even when a thrust bearing fails.

   • The bearing classification for the upper crankshaft bearings in the crankshaft bearing cap is marked on the crankshaft. The first digit indicates bearing cap No. 1, the second digit for bearing cap No. 2, and so on. In the example shown bearing No. 1 starting at the output end has the classification 1, bearing No. 2 the classification 2, and so on. The code letter K indicates the clutch end.

     

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     *1	Crankshaft	-	-
     *a	Bearing Classification	*b	Code letter "K" indicates clutch end.

   • The bearing classification for the lower crankshaft bearings in the bearing seat is marked on the cylinder block. If there is a "K" before the digits, the classification is started at the clutch end. In this case, the first digit indicates bearing No. 5. The fifth digit then indicates bearing No. 1. If there is no "K" before the digits on the cylinder block, the first digit indicates bearing No. 1, and so on. The zeros at the beginning and the end are omitted.

     

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     *1	Cylinder Block	-	-
     *a	Bearing Classification	*b	Code letter "K" indicates clutch end.

   • For details of the installation of the crankshaft bearings, refer to the Repair Manual.

Connecting Rod Sub-assembly and Connecting Rod Bearing

1. A connecting rod made of forged steel (C70) is used.

2. The connecting rods are manufactured by drop forging and then cracked.

   
   

   1. The connecting rod and the connecting rod bearing cap are integrally cast and the connecting rod big end bore is created.

   2. In the case of a cracked connecting rod, the connecting rod big end bore is separated by breaking. A notch is applied with a laser at the predetermined breaking point for this purpose. Then, the connecting rod big end bore is gripped on a 2-part expanding device and separated by driving in a wedge.

   3. The process of cracking (breaking) the connecting rod bearing cap creates a fine fracture surface on the steel connecting rod. This surface structure centers the connecting rod bearing cap to a precise fit when it is mounted on the connecting rod.

   4. The advantage of cracking is that the separation surface does not need to be machined further. The 2 halves fit exactly on each other. Positioning with a fitting sleeve or screw is not necessary.

   Tech Tips

   
   

   • If a connecting rod bearing cap is mounted the wrong way round or on another connecting rod, the fracture structure of both parts is destroyed and the cap is not centered. In this event, the entire connecting rod set must be replaced by new parts.

   • The connecting rod and the connecting rod bearing cap are classified according to weight class. Only connecting rods of the same weight class may be installed in an engine. For details, refer to the Repair Manual.

3. Plastic region tightening bolts are used for the connecting rod.

4. Different connecting rod bearings are used on the connecting rod and bearing cap sides.

   
   

   1. A sputter bearing is used as the connecting rod bearing on the side of the connecting rod which is subject to a high load. This is a tri-metal bearing with a sputtered running layer with a high load capability. The sputtered running layer is created by separating fine particles from a coating material through a vacuum process. These particles are then applied to the running layer of the tri-metal bearing with the aid of electromagnetic fields. This process is called sputtering. The sputtered running layer is characterized by an optimum distribution of the individual elements.

   2. As a softer bearing is always used on the bearing cap side, another tri-metal bearing without a sputtered running layer is used. The soft material of this tri-metal bearing is able to absorb dirt particles. This is very important to avoid bearing damage.

   Tech Tips

   
   

   • It is extremely important to handle the bearings with care, as the very thin bearing metal is not able to compensate for plastic deformations.

   • Sputter bearings can be identified from an "S" imprinted on the back of the bearing cap.

   

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   *1	Connecting Rod	*2	Connecting Rod Bearing (Sputter Bearing)
   *3	Connecting Rod Bearing	*4	Connecting Rod Bearing Cap
   *5	Plastic Region Tightening Bolt	*6	Plain Bearing
   *a	Connecting Rod Small End Bore	*b	Connecting Rod Big End Bore
   *c	Steel Backing	*d	Leaded Bronze or High-strength Aluminum Alloy
   *e	Sputtered Running Layer	-	-

Piston

1. A piston provided with a combustion chamber is used.

2. The piston is made of aluminum-silicon alloy.

3. A cooling channel has been provided to reduce the piston temperature and achieve high reliability.

4. The top ring groove uses a cast-in ring carrier to improve wear resistance.

5. A graphite (graphal procedure) coating is applied to the piston skirt portion in order to achieve friction loss reduction.

6. The top inner edge of the No. 1 compression ring is chamfered. The outer surface of the No. 1 compression ring is polished and slightly crowned. The No. 1 compression ring has a chrome ceramic layer for low wear.

7. The No. 2 compression ring has a sharp lower edge which gives the ring an oil-stripping effect.

8. The running surface of the oil ring is chromium-coated.

   

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   *1	Piston	*2	No. 1 Compression Ring
   *3	No. 2 Compression Ring	*4	Oil Ring
   *5	Piston Pin	-	-
   *a	Piston Skirt	*b	Cooling Channel
   *c	Top Ring Groove	*d	Combustion Chamber

9. The piston is cooled by the engine oil injected by the No. 1 oil nozzle sub-assembly.

   

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   *1	Piston	*2	No. 1 Oil Nozzle Sub-assembly
   *a	Drain Bore	*b	Cooling Channel
   	Engine Oil	-	-

Crankshaft Pulley (Torsional Vibration Damper)

1. A crankshaft pulley (torsional vibration damper) consists of a torsional vibration damper hub, rubber isolation element, belt pulley, plain bearing, flywheel mass, belt pulley rubber isolation element and belt pulley hub.

2. The torsional vibration damper hub and flywheel mass are connected by the rubber isolation element (vulcanized). Therefore, they can be rotated by a few angular degrees with respect to each other. The belt pulley hub is bolted to the front end face of the crankshaft. The torsional vibration damper reduces torsional vibrations of the crankshaft. This reduces the load on the crankshaft and the driven ancillary components.

3. The crankshaft pulley (torsional vibration damper) is important not only for to the smooth running of the engine, but also for the smooth and low-wear driving of the camshafts. The belt pulley is isolated by the rubber isolation element of the belt pulley hub. The rubber isolation element permits greater rotation, and reduces the remaining irregular rotation and thereby the load on the belt drive. The belt pulley is supported by the plain bearing.

   

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   *1	Torsional Vibration Damper Hub	*2	Rubber Isolation Element
   *3	Belt Pulley	*4	Plain Bearing
   *5	Flywheel Mass	*6	Belt Pulley Rubber Isolation Element
   *7	Belt Pulley Hub	-	-

Flywheel

1. A dual-mass flywheel is used to absorb irregular rotations during the engine's combustion process, smoothly transmitting power to the manual transaxle.

2. The 2 isolated masses are connected by way of a spring/damping system. A clutch disc without a torsional vibration damper between the secondary mass and the transaxle assumes the function of disconnecting and connecting. While the flywheel mass which is connected to the engine absorbs the irregularities of the engine, the speed of the mass which is connected to the transaxle does not change as long as the engine speed remains the same. This process of isolation prevents transaxle chatter in the critical engine speed ranges.

3. The graphic on the left shows the irregular rotation of the engine which is applied to the dual-mass flywheel. The graphic on the right shows the irregular rotation which is transmitted to the transaxle. As the 2 graphics show, the irregular rotation is significantly reduced by the dual-mass flywheel.

   

Valve Mechanism

1. Each cylinder of this engine has 2 intake valves and 2 exhaust valves. Intake and exhaust efficiency is increased due to the larger total port areas.

2. This engine uses a valve rocker arm sub-assembly with built-in needle bearings in order to reduce the friction that occurs between the cams and the areas (valve rocker arm sub-assembly) that push the valves down, thus improving fuel economy.

3. A valve lash adjuster assembly, which maintains a constant valve clearance of zero through the use of oil pressure and spring force, is used.

4. The camshaft (intake camshaft) is driven by the No. 1 chain sub-assembly (No. 1 timing chain), while the No. 2 camshaft (exhaust camshaft) is driven through the gear on the camshaft (intake camshaft).

5. The supply pump assembly is driven by the No. 2 chain sub-assembly (No. 2 timing chain).

6. The oil pump with vacuum pump assembly is driven by the oil pump drive chain sub-assembly.

   

   Text in Illustration

   *1	Camshaft (Intake Camshaft)	*2	Valve Rocker Arm Sub-assembly
   *3	Valve Lash Adjuster Assembly	*4	Intake Valve
   *5	Valve Spring Retainer Lock	*6	Valve Spring
   *7	Valve Spring Retainer	*8	Valve Stem Oil Seal
   *9	Exhaust Valve	*10	No. 2 Camshaft (Exhaust Camshaft)
   *11	No. 2 Camshaft Timing Gear	*12	No. 1 Chain Tensioner
   *13	No. 2 Chain Tensioner	*14	No. 2 Chain Slipper
   *15	Oil Pump Drive Chain Sub-assembly	*16	Oil Pump Sprocket
   *17	Crankshaft	*18	No. 2 Chain Damper
   *19	No. 2 Oil Nozzle Sub-assembly	*20	No. 2 Chain Sub-assembly (No. 2 Timing Chain)
   *21	Supply Pump Drive Sprocket	*22	No. 1 Chain Damper
   *23	No. 1 Chain Slipper	*24	Camshaft Timing Sprocket
   *25	No. 1 Chain Sub-assembly (No. 1 Timing Chain)	*26	Camshaft Timing Gear

Chain Sub-assembly (Timing Chain) and Chain Tensioner Assembly

1. Simple sleeve-type chains are used for all chains. On a sleeve-type chain, the tooth flanks of the sprocket always touch the fixed sleeves at the same point. It is therefore particularly important for such chain drives to be correctly lubricated. While having the same pitch and breaking force, sleeve-type chains have a larger link surface than the equivalent roller-type chains. A larger link surface delivers a lower link surface contact pressure and thus less wear in the links.

2. The timing chain is lubricated by the oil No. 2 oil nozzle sub-assembly.

3. The chain tensioners use an oil pressure to maintain proper chain tension at all times. The chain tensioner suppresses noise generated by the chain. The oil in the chain tensioner achieves directional damping by means of a non-return valve.

   

   Text in Illustration

   *1	No. 1 Chain Sub-assembly (No. 1 Timing Chain)	*2	No. 1 Chain Damper
   *3	Supply Pump Drive Sprocket	*4	No. 2 Chain Sub-assembly (No. 2 Timing Chain)
   *5	No. 2 Oil Nozzle Sub-assembly	*6	No. 2 Chain Damper
   *7	Crankshaft	*8	Oil Pump Drive Chain Sub-sembly
   *9	Oil Pump Sprocket	*10	No. 2 Chain Slipper
   *11	No. 2 Chain Tensioner	*12	No. 1 Chain Slipper
   *13	No. 1 Chain Tensioner	*14	No. 2 Camshaft Timing Gear
   *15	Camshaft Timing Gear	*16	Camshaft Timing Sprocket
   *17	Outer Link with Pin	*18	Inner Link with Pressed-in Sleeves

Camshaft

1. The camshaft (intake camshaft) is driven by the No. 1 chain sub-assembly (No. 1 timing chain), while the No. 2 camshaft (exhaust camshaft) is driven through the gear on the camshaft (intake camshaft).

   

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   *1	No. 2 Camshaft (Exhaust Camshaft)	*2	Camshaft (Intake Camshaft)
   *3	Camshaft Timing Gear	*4	No. 2 Camshaft Timing Gear

Valve Lash Adjuster Assembly

1. The valve lash adjuster assembly, which is located at the fulcrum of the valve rocker arm sub-assembly, consists primarily of a plunger, a plunger spring, a check ball and a check ball spring.

2. The engine oil supplied by the cylinder head sub-assembly and the built-in spring actuates the valve lash adjuster assembly. The oil pressure and the spring force that act on the plunger push the valve rocker arm sub-assembly against the cam, in order to adjust the valve clearance created during the opening and closing of the valve. As a result, engine noise has been reduced.

   

   Text in Illustration

   *1	Valve Lash Adjuster Assembly	*2	Plunger
   *3	Check Ball	*4	Plunger Spring
   *5	Check Ball Spring	*6	Cam
   *7	Valve Rocker Arm Sub-assembly	-	-
   *a	Oil Hole	*b	Oil Passage

V-ribbed Belt

1. Accessory components are driven by a V-ribbed belt.

2. An automatic tensioner eliminates the need for tension adjustment.

   

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   *A	Models with Air Conditioning System	-	-
   *1	V-ribbed Belt	*2	Idler Pulley
   *3	Automatic Tensioner Pulley	*4	Crankshaft Pulley (Torsional Vibration Damper)
   *5	Air Conditioning Compressor Pulley	*6	Water Pump Pulley
   *7	Alternator Pulley	-	-