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Adjusting Fuel Injection Timing Engine Dozer D 85 SS - 2 Komatsu

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Adjusting Fuel Injection Timing Engine Dozer D 85 SS - 2 Komatsu


There are two ways for checking and adjusting the fuel injection timing of an injection pump.

  • The  " Match Mark Alignment " method , which is used when the injection pump is installed to the original engine and the pump is not being reaired.

  • The " Delivery Valve " method , Which is used when a repaired or replace injection pump is installed to the engine.  Before inspecting and adjusting the fuel injection timing , bring no. 1 cylinder piston to the top dead center of the comprrssion stroke .For details , see Adjusting valve valve clearance.

Checking And Adjusting By The Match Mark Alignment .

  • With no. 1 cylinder piston at TOP position ,rotate the crankshaft 30° to 40° in the reverse direction.
Adjusting Fuel Injection Timing Engine Dozer D 85 SS - 2 Komatsu

Picture 1
Adjusting Fuel Injection Timing Engine Dozer D 85 SS - 2 Komatsu


  • Align the injection timing stamp line on crankshaft damper ( 1 ) with pointer ( 2 ) by slowly rotating the crankshaft in the normal direction.

Adjusting Fuel Injection Timing Engine Dozer D 85 SS - 2 Komatsu

Picture 2
Adjusting Fuel Injection Timing Engine Dozer D 85 SS - 2 Komatsu


  • Confirm that stamp line a on the injection pump is aligned with stamp line b on the coupling . If the stamp line are out aligment loosen nut ( 3 ) ,align the stamp lines by shifting the coupling and thigtening the nut 58,2 - 62,2 Nm ( 6 kgm ).



Checking And Adjusting By The Delivery Valve Method.

  • Disconect fuel injection pipe ( 4 ) for the no 1 cylinder.
Adjusting Fuel Injection Timing Engine Dozer D 85 SS - 2 Komatsu

Picture 3
Adjusting Fuel Injection Timing Engine Dozer D 85 SS - 2 Komatsu

  • Remove delivery valve holder ( 5 ).
  • Remove Spring ( 6 ) and delivery valve  ( 7 ) from the delivery valve holder , and reasemble the delivery valve holder.

Picture 4
Adjusting Fuel Injection Timing Engine Dozer D 85 SS - 2 Komatsu


  • Place the fuel control lever in FULL position, slowly rotate the crankshaft in the normal direction while operating the priming pump. And observe the position when the fuel stops flowing out of the delivery valve holder.
  • In the position where the outflow of fuel stops, check the injection timing stamp line on the crankshaft damper to see if it is aligned with the pointer. If the injection timing stamp line the passed through the pointer,the injection timing is late. If the injection timing stamp line did not reach the pointer, the injection timing is advance. If the inspection shows that the injection timing is out of adjustment , adjust the fuel injection timing in the following manner. After the checking and adjusting , be sure to reassemble the spring and the delivery valve line.
    1. Rotate the crankshaft 30° to 40° in the revers direction, starting from top position in no 1 cylinder 
    2. Align the injection timing stamp line on damper ( 1 ) with pointer ( 2 ) by slowly rotating the crankshaft in the normal direction.
    3. Loosen nut ( 3 ) on the injection pump mounting flange slot , and rotate the flange on the pump side little by little by operating the priming pump until no fuel flows out the delivery valve holder.

    1. Tighten the nut on the injection pump mounting flange slot ( nut : 58,7 - 62,7 Nm / 6,2 kgm )

    1. Aligh macth mark a with mark b and stamp the marks.