Nissan Pick-ups and Pathfinder 1970-1988

Diesel Fuel Injection

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IDLE SPEED ADJUSTMENT PROCEDURE



See Figures 1, 2, 3 and 4

A special diesel tachometer will be required for this procedure. A normal tachometer will not work.

  1. Make sure all electrical accessories are turned off.
  2.  
  3. Start the engine and run until it reaches the normal operating temperature.
  4.  
  5. The automatic transmission (if so equipped) should be in D with the parking brake on and the wheels blocked.
  6.  
  7. Attach the diesel tachometer's pick-up to the No. 1 injection tube.
  8.  

In order to obtain a more accurate reading of the idle speed, you may wish to remove all the clamps on the No. 1 injection tube.

  1. Run the engine at about 2000 rpm for two minutes under no-load conditions.
  2.  
  3. Slow the engine down to idle speed for about 1 min. and then check the idle.
  4.  
  5. If the engine is not idling at the proper speed, push the throttle control knob (under dash) all the way in on the SD22.
  6.  
  7. Loosen the idle screw locknut. Start the engine again and turn the adjusting screw until the proper idle is obtained. Stop the engine.
  8.  
  9. Tighten the idle adjusting screw locknut, then disconnect the tachometer.
  10.  



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Fig. Fig. 1: Connect a diesel tachometer to the No. 1 injection tube



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Fig. Fig. 2: Push the throttle control knob all the way in-SD22 engine



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Fig. Fig. 3: Idle speed adjustment-SD22 and SD25 (720-D series) engines



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Fig. Fig. 4: Idle speed adjustment-SD25 (D21-D series) engines

DASH POT ADJUSTMENT PROCEDURE



See Figure 5

A special diesel tachometer will be required for this procedure. A normal tachometer will not work.

  1. Make sure all electrical accessories are turned off.
  2.  
  3. Start the engine and run it until it reaches the normal operating temperature.
  4.  
  5. The automatic transmission (if so equipped) should be in D with the parking brake on and the wheels blocked.
  6.  
  7. Attach the diesel tachometer's pick-up to the No. 1 injection tube.
  8.  

In order to obtain a more accurate reading of the idle speed, you may wish to remove all the clamps on the No. 1 injection tube.

  1. Loosen the dash pot locknut.
  2.  
  3. With the engine speed at 1280-1350 rpm, operate and adjust the dash pot so that the control lever tip contacts the dash pot tip.
  4.  
  5. Tighten the locknut, disconnect the tachometer and road test the truck.
  6.  



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Fig. Fig. 5: Dash pot adjustment-SD22 and SD25 engines

 
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