To describe a standard operating procedure for the breakdown rectification of the diesel generator.
1.0 PURPOSE:
To describe a standard operating procedure for the breakdown rectification of the diesel generator.
2.0 SCOPE:
The standard operating procedure describes in detail the method for the breakdown rectification of the diesel generator.
3.0 RESPONSIBILITY:
The responsibility of the breakdown rectification of diesel generator lies with the staff of rank not lower than the junior utility operator.
The responsibility of preparing, reviewing and approving the standard operating procedure lies with the Manager - Maintenance, Head of Production and Head of QAD respectively.
4.0 METHOD:
4.1 Hard starting or does not start.
4.1.1 Checking the Electrical system.
4.1.1.1 If the battery voltage is less than 11.0 Volts/battery, replace with new or charge batteries.
4.1.1.2 If the carbon brushes of the self starter are worn, replace with new brushes.
4.1.1.3 Clean the connector of self starter with carbon tetrachloride to free from foreign particles.
4.1.1.4 Remove the self starter contacts, service them by using emery paper or if the contacts are worn out replace the contacts.
4.1.1.5 Replace the distorted wires and rectify loose connection if any.
4.1.1.6 Check all safety cut-out switches as given below in 4.1.1.6a to 4.1.1.6d.
4.1.1.6a The high water temperature cut-out should be in "NC" position.
4.1.1.6b The low oil pressure cut-out should be in "NO" position.
4.1.1.6c The high RPM cut-out switch should be in "NC" position.
4.1.1.6d Replace the cut-outs if found defective.
4.1.2 Checking of fuel system.
4.1.2.1 Open and ensure that the diesel tank outlet valve is opened fully.
4.1.2.2 Clean thoroughly the whole diesel line from tank to diesel pump with cotton waste and observe for leakage of diesel. Rectify if any.
4.1.2.3 Drian a 1/4 L. diesel from water separator into a small waste oil bowl.
4.1.2.4 Remove the inlet hose of diesel filter and ensure the flow of diesel is flowing without any obstruction. Remove the obstruction if any.
4.1.2.5 Loosen the diesel filter body head. Remove the inlet diesel hose of the governor and fill the hose with diesel till the diesel overflow from the filter body.
4.1.2.6 Tighten the filter body head. Fill the diesel in the hose till the neck level and refix the hose to the governor.
4.1.2.7 Swing the generator governor and diesel pump connecting rod 10 to 15 times.
4.1.2.8 Measure the oil in the governor. It should be in between "H" and "L" marking of the dip rod.
4.1.2.9 If the governor oil is found thick or dirty, replace with fresh oil.
4.1.2.10 Ensure the diesel solenoid is under working condition by operating the generator starting key.
4.1.3 Engine air intake.
4.1.3.1 Open the air filter and service the air filter as given in this SOP steps from 4.7.1 to 4.7.17.
4.1.3.2 Open the generator inlet air passage line and clean with a cloth and refix.
4.1.3.3 Remove and clean the generator breather with diesel.
4.1.4 Start the generator, if the generator does not start or hard starting follow step No. 4.8 under mentioned.
4.2 Low oil pressure.
4.2.1 Ensure the oil pressure gauge is in good working condition by replacing the gauge with another.
4.2.2 Ensure that the hose connected to the oil pressure does not consist of any obstruction by removing the hose and observing it visually.
4.2.3 Inspect oil level, the oil should be in between "L" and "H" markings of the dip rod. Add oil if found low.
4.2.4 Inspect the condition of the oil. Replace the oil and oil filters if the old oil is thick or dirty.
4.2.5 Observe the whole generator and identify any oil leaks from head gasket, oil sump gasket, front bearings, rear bearings etc.
4.2.6 If the problem is not rectified still, follow step No.4.8.
4.3 High water/oil temperature.
4.3.1 Inspect crank case oil level. Add oil if found low.
4.3.2 If the crank case oil level is too high flush out oil to the required level.
4.3.3 Inspect radiator water level. Add DM water if found low.
4.3.4 Check the hardness of the radiator water and adjust the hardness in between 3000 PPM to 5000 PPM by draining the radiator water and changing water corrosive resistor element.
4.3.5 Replace the faulty gauge and thermostats.
4.3.6 Tighten the loose water pump belts and replace the defective belts if any.
4.3.7 Replace the damaged water hose pipes.
4.3.8 Clean the radiator fans with soap solution.
4.3.9 If the water temperature/oil temperature are still raising, follow step No.4.8.
4.4 Generator does not attain 1500 RPM.
4.4.1 Ensure the RPM meter is under working condition. Replace if found faulty.
4.4.2 Check the tachometer cable if found defective replace it.
4.4.3 Check the governor vernier. Replace the defective one.
4.4.4. Check the governor oil level and condition. If the level is low add oil and if the oil is dirty or thick replace the oil.
4.4.5 Check for the free play of connecting rod between governor and fuel pump.
4.4.6 If the RPM still does not raises, follow step No.4.8.
4.5 Voltage does not develops.
4.5.1 Check for faulty voltmeter or selector switch and replace the faulty one.
4.5.2 Rectify loose connections and defective broken wires.
4.5.3 Check the F1 & T1 fuses of the AVR. Replace the burnt fuses.
4.5.4 Disconnect F1 & F2 terminations from the AVR and meggar F1 & F2 for the continuity of field excitation winding. If found defective follow step No.4.8 under mentioned.
4.5.5. If the voltage produced is out of range of 410 +3% adjust the "V-TRIM" till the voltage fall within the range.
4.6. Frequency not developed.
4.6.1 Replace the faulty gauge.
4.6.2 If the frequency produced is less than 50 ± 2 or more than 52 ± 2 when the voltage and RPM are 410 ± 3% and 1500 RPM respectively, adjust QDC potentiometer present in the AVR till the frequency fall within the range.
4.6.3 Still if the frequency is not developed/not correct follow the step No.4.8.
4.7 Servicing of the air filter element.
4.7.1 Stop the generator, if it is in running condition.
4.7.2 Loosen clamp assembly which holds cup assembly to body air cleaner.
4.7.3 Remove cup assembly.
4.7.4 Loosen wing nut of outer element and remove it.
4.7.5 Remove air filter element.
4.7.6 The air filter element may be cleaned several times by using compressed air not exceeding 30 PSI.
4.7.7 Do not hold air jet too close to paper element.
4.7.8 Direct air to element from inside along its folds.
4.7.9 Repeat the step 4.7.8 for 6 times and check the element.
4.7.10 If small holes or thinner parts are found on element when it is checked with an electric bulb after cleaning and drying, replace the element.
4.7.11 Do not use element whose folds or gasket or seal are damaged.
4.7.12 While cleaning element do not heat or beat against something.
4.7.13 Elements that have been cleaned several times will finally clog and air flow to engine would be restricted such elements must be replaced by a new element.
4.7.14 Fix the air filter element.
4.7.15 Place the wing nut and tighten it.
4.7.16 Place the cup assembly.
4.7.17 Place the clamp assembly such that it holds body and cup assembly and tighten the clamp.
4.7.18 Reset the air filter service indicator.
4.8 If there is any breakdown which can not be rectified, take the necessary service from an authorised agency.
5.0 RECORDING
The responsibility of recording the breakdown in the history card lies with the staff of rank not lower than the maintenance supervisor.
Diesel generator, breakdown rectification, engineering
