ENGINE UNIT DETAILS

Cylinder Head

1. The cylinder head is made of aluminum alloy.

2. An injector has been located in the center of the combustion chamber in order to improve engine performance and clean emission.

3. Two intake ports with different shapes have been combined to promote the mixture of fuel and air by optimizing the swirl in the cylinder.

4. A vertical two-stage construction is used for the water jacket to improve cooling performance.

5. A glow plug is placed between the intake ports of each cylinder to ensure startability.

6. The passage for the EGR is provided in the cylinder head. By cooling the exhaust gas, it is possible to recirculate the great amount of exhaust gas.

7. Plastic region tightening bolts are used for the cylinder head.

   

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   *1	Injector Hole	*2	Glow Plug Hole
   *3	Water Jacket	-	-
   *a	View of Back Side	*b	Cylinder Head Cross Section
   	EGR Passage	-	-

Cylinder Head Gasket

1. A steel-laminate type cylinder head gasket is used.

2. A shim has been added around the cylinder bore to increase the sealing surface, thus realizing excellent sealing performance.

   

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   *1	Shim	-	-
   *a	A-A Cross Section	*b	Cylinder Bore Side
   *c	Outer Side	-	-
   	Front	-	-

3. There are 5 sizes of cylinder head gaskets, marked "A", "B", "C", "D" or "E" according to piston protrusion. For details, refer to the Repair Manual.

   

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   Rear

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Cylinder Block

1. The cylinder block is constructed of liner-less cast iron alloy.

2. Ribs have been added to the block of the cylinder block to reduce engine vibration.

   

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   *1

   Rib

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Balance Shaft

1. For in-line 4 cylinder engines, the main cause of vibration is imbalanced inertial force of reciprocating parts such as the pistons and connecting rods. The 1KD-FTV engine vibration has been reduced by using 2 balance shafts to cancel the imbalanced inertial force, thereby reducing engine noise (booming noise).

2. These balance shafts are built into the cylinder block. Driven by the timing gear, the balance shafts rotate at twice the speed of the crankshaft and in the opposite direction of each other.

   

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   *1	No. 1 Balance shaft	*2	Oil Pump Drive Gear
   *3	Crankshaft Timing Gear	*4	Idle Gear
   *5	Supply Pump Drive Gear	*6	No. 2 Balance Shaft

Piston

1. In conjunction with the adoption of direct injection, piston provided with combustion chamber is used.

2. The piston is made of aluminum alloy.

3. A cooling channel has been provided to reduce the piston temperature.

4. The top ring groove uses a Ni-resist cast iron ring carrier to improve wear resistance.

5. The piston skirt has been coated with resin to reduce friction loss and improve initial seizure resistance.

6. A PVD (Physical Vapor Deposition) coating has been applied to the surface of the No. 1 compression ring, in order to improve its wear resistance.

   

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   *1	No. 1 Compression Ring	*2	No. 2 Compression Ring
   *3	Oil Ring	-	-
   *a	Ni-resist Cast Iron Ring Carrier	*b	Cooling Channel
   *c	PVD Coating	*d	Resin Coating

Connecting Rod and Connecting Rod Bearing

1. The connecting rods are made of high-strength material to ensure the proper strength.

2. Knock pins are used at the mating surfaces of the bearing caps of the connecting rod to minimize the shifting of the bearing caps during assembly.

3. Plastic region tightening bolts are used.

4. An aluminum bearing is used for the connecting rod bearings.

   

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   *1	Knock Pin	*2	Plastic Region Tightening Bolt
   *3	Connecting Rod Bearing	-	-

Crankshaft and Crankshaft Bearing

1. The crankshaft has 5 journals and 8 balance weights.

2. All pins and journal fillets are roll-finished to maintain adequate strength.

3. The lining surface of the crankshaft bearing has been boring-processed to realize an optimal amount of oil clearance. As a result, cold-engine cranking performance has been improved and engine vibrations have been reduced.

4. The upper main bearing has an oil groove around its inside circumference.

   

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   *1	Upper Main Bearing	*2	Lower Main Bearing
   *a	Roll-finished	*b	Oil Hole
   *c	Boring-processed	*d	Oil Groove

Crankshaft Pulley

1. The rigidity of the torsional damper rubber has been optimized to reduce noise.

   

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   *1

   Torsional Damper Rubber

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Valve Mechanism

1. Each cylinder has 2 intake valves and 2 exhaust valves. Intake and exhaust efficiency is increased by means of the larger total port areas.

2. The valves are directly opened and closed by 2 camshafts.

3. The intake camshaft is driven by a timing belt, while the exhaust camshaft is driven through a gear on the intake camshaft. A small-diameter, flat-teeth gear is used for driving the exhaust camshaft in order to reduce gear noise.

   

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   *1	Timing Belt	*2	Exhaust Camshaft Driven Gear
   *3	Exhaust Camshaft Drive Gear	*4	Exhaust Camshaft
   *5	Intake Camshaft	-	-

   

Camshaft

1. The cam nose has been chill-treated to increase its abrasion resistance.

   

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   *1	Exhaust Camshaft Driven Gear	*2	Exhaust Camshaft
   *3	Exhaust Camshaft Drive Gear	*4	Intake Camshaft
   	Chill Treated	-	-

Intake and Exhaust Valves

1. Along with the increased amount of valve lift, shim-less valve lifters that provide a large cam contact surface are used.

2. The adjustment of the valve clearance is accomplished by selecting and replacing with appropriate valve lifters.

   

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   *1

   Valve Lifter

   *2

   Camshaft

   Tech Tips

   The valve lifters must be replaced when it is necessary to adjust the valve clearance. For this purpose, valve lifters with different thickness are available as service parts. For details, refer to the Repair Manual.

Timing Gear Train

1. The supply pump, vacuum pump, oil pump and balance shafts are driven by the crankshaft timing gear.

2. The idle gear is constructed with a scissors gear on its front and back to reduce noise.

   

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   *1	No. 2 Camshaft Timing Pulley	*2	Automatic Tensioner
   *3	No. 1 Camshaft Timing Pulley	*4	Oil Pump Drive Gear
   *5	Balance Shaft Drive Gear	*6	Supply Pump Drive Gear
   *7	Crankshaft Timing Gear	*8	Idle Gear
   *9	Vacuum Pump Drive Gear	-	-

Serpentine Belt Drive System

1. A serpentine belt drive system, which drives all accessory components by a single V-ribbed belt, is used. It reduces the overall engine length, weight and number of engine parts.

2. An automatic tensioner is used. This makes the tension adjustment unnecessary.

   

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   *1	Alternator Pulley	*2	Automatic Tensioner
   *3	Crankshaft Pulley	*4	Water Pump Pulley