Chrysler RAM50/D50/Arrow 1979-1993 Repair Guide

Injection Pump

Print

REMOVAL & INSTALLATION




WARNING
After the pump is reinstalled, the injection timing must be reset. Adjusting the injection timing requires special tools for measuring the prestroke of the pump. If these tools are not available, do NOT remove the injection pump or attempt to work on it. See Figure 1

  1. Disconnect The battery ground cable.
  2.  
  3. Remove the upper cover from the timing belt.
  4.  
  5. Remove the nut and washer holding the injection pump sprocket to its shaft.
  6.  

Be careful not to drop the nut and/or washer into the lower timing cover.

  1. Turn the crankshaft to bring the No.1 piston to TDC/compression. When the piston is in this position, all the timing marks align.
  2.  



Click image to see an enlarged view

Fig. Fig. 1: The diesel fuel injection pump

  1. Use a pulley puller or extractor to carefully remove the injection pump sprocket. Catch the small Woodruff key and don't lose it.
  2.  


WARNING
Do not subject the shaft to impact. Protect the timing belt from any stress, twisting or fluids. After the sprocket is removed, do not turn the crankshaft.

  1. Disconnect the boost compensator hose at the injector pump.
  2.  
  3. Remove the vacuum hose from the vacuum regulating valve and the injection pump.
  4.  
  5. Disconnect the electrical harness running to the pump.
  6.  
  7. Wrap the joints with rags or cloth and remove the fuel supply hose and the return hose from the injection pump and plug the ports immediately. Fuel will be released when these joints are opened.
  8.  
  9. Loosen the union nuts and remove the injection lines. Use a second wrench to counterhold fittings where possible.
  10.  
  11. Remove the two mounting bolts, then remove the mounting nuts and washers.
  12.  

The pump is heavy and awkward to hold; make sure you or a helper have a firm grip before releasing the mounts.


WARNING
Do not hold the pump by either the accelerator lever or the fast idle lever. Additionally, these levers must not be removed from the pump. The levers' adjustment and placement is critical to the correct operation of the pump.

  1. Remove the injection pump mounting bracket from the engine.
  2.  
  3. Before reinstalling the pump, make certain the entire pump is clean and the lines have been checked for dirt and foreign matter.
  4.  
  5. Install the mounting bracket on the engine and tighten the bolts to 26 ft. lbs. (35 Nm).
  6.  
  7. Carefully mount the pump and tighten the nuts and bolts to 19 ft. lbs. (26 Nm).
  8.  
  9. Install the fuel delivery lines. Counterhold the joint while tightening the line fittings to 22 ft. lbs.(29 Nm).
  10.  
  11. Carefully connect the fuel supply hose and the return hose to the pump.
  12.  
  13. Connect the wiring harness to the pump.
  14.  
  15. Install the vacuum hoses between the regulating valve and the injection pump.
  16.  
  17. Connect the boost compensator hose and connect the negative battery cable.
  18.  
  19. Carefully install the sprocket on the shaft of the injection pump. Do not subject the shaft to impact and do not damage the timing belt. Make sure the Woodruff key is correctly seated in its groove.
  20.  
  21. Perform the ignition timing adjustment procedure outlined in this section.
  22.  


WARNING
This adjustment MUST be performed each time the injection pump is removed.

  1. Bleed the fuel system.
  2.  
  3. Install the upper timing belt cover.
  4.  

TIMING ADJUSTMENT



See Figures 2, 3 and 4


WARNING
The use of the correct special tools or their equivalent is REQUIRED for this procedure. The timing cannot be adjusted without tool MD998384, the prestroke measuring adapter. If this tool is not available, do not attempt to adjust the injection timing.



Click image to see an enlarged view

Fig. Fig. 2: Special tool MD998384 or equivalent is needed to check the injection timing



Click image to see an enlarged view

Fig. Fig. 3: Remove the timing check plug from the injection pump head



Click image to see an enlarged view

Fig. Fig. 4: Attaching the prestroke measuring adapter

  1. With the engine off, turn the crankshaft clockwise until all the timing marks align. This places the engine at TDC/compression for No.1 piston.
  2.  
  3. Loosen but do not remove the injection pipe union nuts at the injection pump. Always use a second wrench to counterhold the pump fitting.
  4.  
  5. Loosen the nuts and bolts holding the injection pump to the engine but do not remove them.
  6.  
  7. Examine the special tool and make certain the tip protrudes 0.4 in. (10mm). The pushrod can be adjusted by the inner nut.
  8.  
  9. Remove the timing check plug from the injector pump head and install the prestroke measuring adapter and a dial indicator.
  10.  
  11. Carefully turn the crankshaft counterclockwise until the notch on the pulley is at a point about 30° before the TDC mark. The notch should be in roughly the 11 o'clock position.
  12.  
  13. Zero the dial indicator. With a wrench, slightly move the crankshaft in both the clockwise and counterclockwise directions. The dial indicator should stay at zero; if it changes with engine movement, the initial 30° setting was incorrect. Repeat steps 6 and 7 until the gentle movement of the crankshaft does not move the pointer on the dial indicator.
  14.  
  15. Turn the crankshaft clockwise until the notch in the pulley aligns with the 5° ATDC mark. At this point, the dial indicator should read 0.0383-0.0405 in. (0.997-1.003mm).
  16.  
  17. If the gauge does not show the specified value, move the injection pump body right or left on the mounts until the dial indicator reads correctly. Tighten the mounting nuts and bolts to hold the pump in place.
  18.  
  19. After the pump is locked in place, repeat the check procedure. Set the engine 30° before, zero the indicator, move the engine to 5° ATDC and check for the correct gauge reading. Each time the pump is moved, the entire check should be repeated.
  20.  
  21. Remove the special tools. Install a new copper gasket and the timing check plug. Tighten it to 6 ft. lbs. (8 Nm). Do not overtighten this bolt.
  22.  
  23. Tighten the fuel delivery lines. Counterhold the joint while tightening the line fittings to 22 ft. lbs. (29 Nm).
  24.  
  25. Since the fuel lines were loosened, bleeding the system is recommended.
  26.  

 
label.common.footer.alt.autozoneLogo