To ensure normal operation of the engine and to obtain the best economical fuel consumption and good combustion, injection timing should be checked and readjusted after every 500 operating hours and whenever the engine has been dismantled and reassembled.
To adjust injection timing, remove the high pressure fuel piping of the first cylinder and turn the crankshaft until the piston of the first cylinder is at the beginning of its expansion stroke. (To determine whether it is at the beginning of its expansion stroke, turn the crankshaft slightly and observe the movement of the valves. If the valves remain still when the crankshaft is slightly turned, it indicates that the first cylinder is at the beginning of its expansion stroke. ) Check the timing pointer on the flywheel housing which should point at the “0” mark on the rim of the flywheel. At this position, the plunger spring of the first pump element of the injection pump should be compressed. (This can be checked by removing the B-type injection pump inspection door cover.) Then turn the crankshaft in the direction opposite to that of its rotation about 40°. After this, turn the crankshaft slowly and smoothly in the direction of its rotation and observe the fuel level in the fuel outlet of the delivery valve holder of the first pump element at the same time. When this fuel level just starts to rise, stop turning the crankshaft immediately. This is the beginning of injection of the first cylinder whose angle can be read out from the degree marking on the flywheel rim at which the timing pointer points. The angle at which injection begins should be at the range of technical parameter of the relevant model diesel engine. If it is not within this limit, it can be adjusted by loosening the two screws（Fig.1 item C）on the injection pump coupling and turn the crankshaft till the coupling has turned the required angle. After adjustment, tighten the two screws and check the injection timing again.
Another way to adjust the injection timing is to turn the injection pump coupling. Turn the crankshaft until the piston of the first cylinder is at the beginning of its expansion stroke. Then turn the crankshaft in the direction opposite to that of its rotation till the timing pointer on the flywheel housing is relevant mark. Remove the injection pump inspection door cover and loosen the two screws on the injection pump coupling. Turn the injection pump camshaft in the direction of its rotation till fuel level in fuel outlet of the delivery valve holder of the first pump element just stars to rise. Then tighten the coupling screws and check the beginning of injection again. The beginning of injection should also be within the range of technical parameter of the relevant model diesel engine.http://www.wandiengine.com/