A diesel genset is a specialized piece of engineering and it needs specialized upkeep and maintenance. And one of the many ways to ensure that it keeps performing to its optimum standards is to change the oil filter regularly.
The frequency of oil filter change depends on the size of the generator.
Cleaning the Centrifugal Lubricating Oil Filter
Before you begin the process of changing the filter, it is recommended that you switch off the engine and allow time for lubricating oil to go back to sump.
Ø Remove the cover nut and lift off the filter body cover.
Ø Check the "O" ring for damage and change if required.
Ø Remove the rotor assembly from the spindle and wait for the oil to drain from the nozzle before detaching from the filter body. Hold the rotor body firmly and remove the rotor knurled nut. Separate the rotor cover from the rotor body. Remove the central stand tube.
Ø Clean the sludge from the inside of the rotor cover with a wooden implement. Make sure it is wiped clean.
Ø Clean and wash out the central stand tube using an approved solvent - make certain that the strainer holes are not blocked.
Ø Clean out nozzles with a brass wire to ensure smooth and free passage of oil. Check the top and bottom bearings in the rotor body - they should be free from damage and/or excessive wear and tear.
Ø Completely Reassemble the rotor. Tighten cover nut to 9.5 Nm - 10.8 Nm (7-8 lbft.)
Ø Closely check the spindle journals - they shouldn’t be any damage or excessive wear. Then remove the cut-off valve plug from the filters only and the cut-off valve assembly. Make sure that the spring and shuttle are in good condition and move without any hindrance. Examine the gasket and replace if damaged or worn out.
Ø Re-assemble cut-off valve assembly.
Ø Re-assemble the filter fully. It is important to make sure that the rotor assembly is free to rotate. Now, replace the filter cover and tighten the cover nut.
Ø Switch on the engine and with the engine running check all connections and joints for any leakage.
Cleaning Engine Oil and Standard Spin-On Type Lubricating Oil Filters
Switch off the engine and place a container of at least 148 litres capacity (32.5 gal) below the drain plug.
Now remove the drain plug and allow the oil to drain.
It is advised that this procedure be best carried out while the engine is still warm - the thinner oil will drain more efficiently. As the oil is draining, remove the three oil filters by turning them clockwise with a strap wrench.
Wipe the sealing faces and threaded bosses of the oil header. Smear engine oil on the captive rubber sealing ring and carefully screw each new filter using firm hand pressure only.
Refit the drain plug and fill the engine with the appropriate grade of new oil. Manually set the air shut off valves to the run position and hold the stop lever in the stop position. Start and crank the engine over until the oil pressure gauge registers 0.4 kg/cm2 (5lb/in2).
Continue cranking for a further 10 seconds - this will ensure that the oil has reached the turbocharger bearings. Stop cranking the engine and visually check the engine for oil leaks, top up the oil level.
Cleaning the Optional Changeover Lubricating Oil Filters
A three-way change-over valve in the head enables the elements to be changed, one at a time, whilst the engine continues to run. They are normally mounted on the engine, but may be remotely mounted, and connected to the engine by means of flexible pipes.
Changing the Filter Elements without Stopping the Engine
The normal position of the change-over valve is the leg of the inverted T pointing upwards - when both filter elements are in circuit. Turning the tine valve so that the leg of the T points to the left, puts the right hand filter out of service - this lets it be replaced by a new filter. Turning the valve so that the leg points to the right, puts the left hand filter out of service, so that this one can now be exchanged with a new filter canister. The valve is then returned to its original position, so that both elements of the filter are back in service.
Remember that regularly changing your oil filters in your diesel gensets will prolong its life.