The second and third order maintenance of the WD305 series diesel engine

- Nov 20, 2017-

1. Second order maintenance

Apart from the items stated in “First order maintenance”, the second order adds 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.


2. Third order maintenance

Apart from the items stated in “Second order maintenance”, the thrid order adds 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.