Checking Exhaust and Electrical System of Diesel Engine

This is the final part of checking and adjusting Deutz 226B series diesel engine for delivery beginning. It mainly includes checking exhaust, turbocharging and inter-cooling system and electrical system. 

3. 9. 2 Exhaust

The three - cylinder or four - cylinder diesel engine adopts unitary exhaust manifold, and the six - cylinder engine adopts inserted exhaust manifold which is made up of two parts ( every part for three cylinders) and sealed with narrow width ring. The joint between exhaust manifold and cylinder head is sealed with stainless steel gasket, the convex surface of which should face to the cylinder head.  The torque for tightening nut is 45 t 5Nm.

The exhaust resistance of diesel engine should be as small as possible; therefore the exhaust manifold must have sufficient sufficient or area and with bends as few as possible, because the performance of engine will be influenced obviously if the exhaust resistance exceeds a certain value. The sum of the resistances of exhaust main and muffler should not be more than 7.5kPa for natural aspirated engine, and not he more than 5kPa for turbocharged engine.

3. 9. 3 Turbocharging and inter - cooling system

Turbocharger: Both turbocharging models and the turbocharging inter - cooling models of the 226B series engine employ the radial flow exhaust turbocharger. See the accessory list for the those models.  The oil lubricating and cooling the turbocharger flows into the turbocharger from the main oil passage then directly back into the crankcase.

The exhaust turbocharger is a kind of running mechanism at its high speed and high temperature. The immediate halt when the engine is running at high speed and with large load is strictly forbidden.  The right way is to decrease the load and the speed gradually and let the engine run idly for another 5 -10 minute so as to avoid any damage to the turbocharger bearing. After the turbocharger is disassembled, some clean engine oil should be put at the oil inlet during the mounting process.

Charging air cooler (intercooler)

The temperature will go up after the air goes through the turbocharger and gets pressured. The intercooler of the 226B turbocharging inter - cooling engine features: air - air cooling. Is used to lower the pressured intake air temperature.

Air - air cooling intercooler ( delivered conforming with the contract) , generally speaking, is assembled together with the circulating water radiator, cooled by fan. The intercooler be placed at the hack of the radiator. The intercooler could also be placed in line with the radiator, determined by the overall fitting mechanism.

The maximum acceptable flow resistance ( supercharger to intercooler/ intercooler to engines) then the pressured air from the supercharger is passing through the pressure pipe should be less than 2kPa. The flow resistance while going through the intercooler should be less than 5.0 - 5. 5 kPa.  So the limit value of the total resistance when the pressured air is passing through pressure pipe and intercooler is 7. 0 - 7. 5 ( kPa) ,

3. 10 Electrical system

The system is consisted of starter, chargeable generator, control instrument and storage battery. The service voltage is 24V or 12V, subject to the choice of the customers.

Starter: the starter is a DC motor controlled by electromagnetism. Without specific requirement, the rated power is 4kW or 6kW at the working voltage of 24V and 2. 7kW or 4kW at the working voltage of 12V.

Generator: The generator is a kind of silicon rectifying generator equipped with transistor adjuster. The rated voltage is 28V or 14V. The generator is connected parallelly with the storage battery.  The generator is self - excited when working.

Storage battery (generally self-prepared by the customers)

Storage battery capacity

Schematic diagram of the electric circuit connection

1. Diesel engine button               11. connecting wire from starting

2. Starter                          12. meter cover

3. Adjustor of the generator           13. ignition lock

4. AC generator                     14. starting button

5. The connecting wire from the AC generator to starter  15. temperature warning light

6. Storage battery                   16. oil pressure warning light

7. The anode connecting wire to the starter 17. charging indicator light

8. Earth wire                         18. temperature sensor

9. Connecting wire from starter to charging indicator 19. oil pressure sensor

10. Connecting wire from starter to ignition lock

Flame preheating unit

Flame preheating unit ( OPT) :the unit is a cold - starting auxiliary equipment used in cold weather and is composed by temperature sensor, solenoid valve,flame preheating plug, electronic control device and preheating indicator fitted to water outlet pipe ( principle diagram  shown in fig27) . The fuel enters preheating plug from the low pressure fuel delivery pipe and is  ignited by electric heating ,and the flame enters air inlet pipe and heats the air . The process is  perform automatically by control system. The unit controls automatically the glowing time and flame preheating time of the preheating plug according to the ambient temperature. The drive can start the engine after the preheating indicator give out signal.

1. Electric control unit A24  2. cooling water pipe of the engine  3. temperature sensor

4. Delivery pipe to high-pressure pump   5. solenoicd valve  6. fuel pipe

7. Air inlet pipe  8. Preheating plug R3 * 9.24 V battery  10. electric key

11. Fuse 25A  12. Preheating indicator 112/29  13. generator   14. start button

3.11 main bolts tightening torque