Main projects of maintenance of the WD305 series diesel engine

- Jan 13, 2018-

For reliable engine operation, all maintenance work must be carried out promptly, carefully and correctly. Must carry out diesel engine technology maintenance system, technical maintenance category below:

1.Daily maintenance (after every work-shift).

2.First order maintenance (after every100 accumulated operating hours).

3.Second order maintenance (after every500 accumulated operating hours).

4.Third order maintenance (after every1000-1500 accumulated operating hours or every 1 years).

No matter what kind of maintenance is carried out, the dismantling, checking and reassembling should always be done in a planned and sequential way. Be sure to use suitable tools and exert proper strength. After dismantling, the surfaces exposed must be kept clean and coated with anti-rusting oil or grease to prevent them from rusting. Take care of the relative positions of the detectable parts, the structural features of the parts which can not be dismantled, the fit clearances and the adjusting methods. At the same time, keep the engine and its accessories clean and complete.

A. Daily maintenance

1.Check lubricating oil level in engine sump. Oil level should meet the marks indicated on the oil level scale. If insufficient, replenish to the specified limit.

2.Check oil, water and gas leakage.

3.Check rigidity and reliability of all components attached to the engine. Check rigidity and reliability of engine foundation bolts and the connection between the engine and the driven machinery.

4.Check all the meters to see whether the readings are normal. If abnormal, replace or repair it.

5.Check injection pump connecting plate. If there is any alteration of injection timing or the joint bolts are loose, check the injection timing and tighten the bolts.

6.Check the connecting screw between turbocharger and its bracket and bust of connection between turbocharger and air inlet pipe to see whether they are loose.

7.Clean the engine and the surface of the attachment. Oil, water and dust gathered on the engine surface, turbocharger, cylinder head cover and air filter can be wiped clean with a dry rag or cloth dipped in a bit of diesel. Clean off the dust gathered on the charging alternator, radiator, intercooler and fan by wiping or blowing with compressed air.

B. First order maintenance

Besides the maintenance work given in “Daily maintenance”, add the following items:

(1) Check the voltage of the battery and specific gravity of the battery acid. The specific gravity of the battery acid should be within 1.28-1.29 (at ambient temperature of 15℃) and should not be lower than 1.27. Check the level of the battery acid which should be 10-15 mm above the pole plates. If insufficient, add distilled water to required level.

(2) Unscrewing oil drain plug on the oil pan. Clean it in fuel. (If the oil is rather clean, its change period can be prolonged).

(3) Fill all grease nipples with the proper grade of grease and fill all oil cups with lubricating oil.

(4) Diesel engine first run accumulate full 50 hours, must be replaced oil filter element; After running accumulate full 150 hours, must be replaced oil filter element to ensure that enter the high pressure oil pump of the diesel cleanness to use requirement, when change, only diesel filter together with shell from the filter holder unscrew and put on the new filter assembly to filter seat, to ensure the seal, when install the new filter, can be on the top of the seal face coated with a small amount of oil, and then screwing in filter in the seat.

(5) Move the turbocharger rotor with hand. If the rotor can not rotate freely and smoothly or stop rotating soon, this means that the bearings may be worn excessively or there occur collision or jam between rotor and its mountings or there may be severe carbon deposit on the air sealing plate of turbo back. In such a case, disassemble the turbocharger and check radial clearance and axial move of rotor to analyze probable causes and remedy them.

(6) Check the tightness of bolts of busts on connection between turbine case and middle case and tighten them if loose.

(7) Disassemble the compressor housing and clean impeller and passage of compressor housing.

(8) Clean air filter and get rid of the dirt in the collector. Take out the filter-element and clean off the dirt by vibrating or blowing with compressed air (its pressure is 98~147kPa) from the center to the outside.

C. Second order maintenance

Apart from the items stated in “First order maintenance”, add the following:

(1) Check the injection pressure and spray pattern of the injectors. If necessary, dismantle the injector, clean the parts and adjust.( This series of diesel injector for injection pressure is 24 MPa)

(2) Check the calibration of the injection pump. If necessary, recalibrate it.

(3) Check valve timing and injection timing. If necessary, adjust these timings.

(4) Dismantle cylinder head. Check seal and wear of valves. Repair if necessary.

(5) Check leakage of fresh water pump. Repair or replace if necessary.

(6) Remove the oil sump and check the cylinder liners for water leakage. If necessary remove the cylinder liner, the liner rubber seal rings should be renewed.

(7) Remove the timing gear case cover and check the transmission mechanism of gear lubrication condition. If the nozzle hole is blocked, probe it with a wire of proper size.

(8) Check the lubricating oil cooler and radiator for oil and water leakage. If necessary, repair.

(9) Check the tightness of the connecting rod bolts, crankshaft bolts and nuts, cylinder head studs and nuts, and main bearing cover bolt. If necessary, remove, check and tighten the rules to torque again.

(10) Check the wiring contacts of the electric system. Burnt marks should be removed.

(11) Clean piping of lubricating oil and fuel system including oil sump, lubricating oil piping, lubricating oil cooler, fuel case and fuel piping. Clean off the dirt and blow them dry.

(12) Clean the cooling system. Compounding and method is described in SECTION II.

(13) Whether it is necessary to disassemble the turbocharger or not can be judged by the running condition of the engine. If necessary, disassemble the turbocharger and do the following work: clean air seal ring and air seal plate of turbo end, clean the dirt and carbon deposits of turbo impeller and inlet shell, clean oil reservoir of middle shell, check the wear of float bearing. Replace the parts if it is seriously worn. Check the wear of oil seal ring and see whether it is distorted and sintered, replace the parts if so.

D. Third order maintenance

Apart from the items stated in “Second order maintenance”, add the following:

(1) Check cylinder head assembly. Check wear of valves, valve seats, valve guides, valve springs, as well as fitting surfaces between push rods and rocker arms. If necessary, repair or replace worn parts.

(2) Check piston and connecting rod assembly. Check wear of piston ring, cylinder liners, and connecting rod bearing and bushing. If necessary, replace worn parts.

(3) Check the crankshaft assembly. Check wear of main journal, connecting rod journal and spindle tile. If necessary, replace worn parts.

(4) Check drive mechanism and remove gearcase. Check wear of tooth surfaces of drive gears and measure their backlashes. If necessary, repair or replace worn parts.

(5) Check fuel injection pump and governor. Check the tightness of oil pump plunger matching parts and governor. If necessary, repair or replace worn parts.

(6) Check lubricating oil pump and fresh water pump. Check and measure parts which are liable to wear. If necessary, readjust.

(7) Check gaskets of cylinder head and intake and exhaust manifolds. Any gasket damaged or has lost its sealing effect should be replaced.

(8) Check charging alternator and starting motor. Clean all parts and bearings, blow them dry and fill with new grease, check wear condition of starting motor pinion and see whether transmission mechanism is running freely.