Removing the Injector Pump

Removing the fuel injector pump was a bitch! Wow. Here ‘goes:

First off, she’s a 3247F190 Delphi Hydraulic Fuel Pump Ser #1245R mounted on the Perkins 4-108. To get to her, you will have to drain the coolant, remove the coolant tank, move the exhaust manifold a few inches out of the way, remove all the high pressure injector lines and disconnect everything hanging off the pump.

  1. Drain the coolant and remove the tank.
    1. The only reason to drain the coolant is so you can remove the coolant tank. So pick anywhere below the tank and gravity will do the work.
    2. Then undo the two bolts holding the cooling tank down
    3. With the tank loose, it’s easier to unstick and remove the hose connections
    4. That’s it. Removing the cooling tank is fairly easy. Check the thermostat while you’re at it.
  2. Move the exhaust manifold out of the way.
    1. To help reach the fuel lines where they connect to the injector pump, you will need more room. But you don’t have to remove the manifold completely; Just enough to work around.
    2. Note that you will need new gaskets before reattaching the manifold.
    3. Slacken the nuts holding the manifold onto the engine block just under the injectors.
    4. You should now be able to move the manifold away from the block a few inches.
  3. Remove the high pressure injector lines
    1. Before this step, ensure your ignition is off. You will be working in close proximity to the starter solenoid which can provide a strong shock if you short it by mistake. Maybe even test it with a multi-meter first just in case.
    2. Also be careful not to drop any foreign matter into the fuel ports. Tiny specks matter. Block off the ports as you go with tape or something.
    3. Undo all four fuel line connections at the fuel injector side.
    4. Then undo the other end of the four lines where they attach to the fuel injector pump.
      1. To get to the hard-to-reach ends, it may help to remove the raw water cooling hose. You’ll know the one. It’s preventing you from getting both hands to the injector pump. Once it’s free you can move it the few inches to get your hands in there.
    5. Slacken all the fuel line fittings on the pump, then snake the four high pressure fuel lines out. Sounds simple, but this step was time intensive and frustrating! Not much room in there, and you may need to buy some shorter crescent wrenches. I went out and bought a set of cheapos just for this one job.
    6. It helps to label them “1” through “4” as well as “top” or “bottom” to hasten the reassembly, then lay them aside.
    7. There should be a total of six ports on the pump: Four high pressure lines, the low pressure “in” and the low pressure “fuel return.”
    8. Also disconnect the fuel cutoff spring and throttle linkages.
    9. And now, VERY IMPORTANT! Mark the alignment. If there isn’t already, cut a fine line using a razor knife on the engine block directly beside the alignment mark on the pump. Pen wears off. These marks are used for fine-tuning the timing of the pump and you don’t want to go through the alignment process. If the engine ran fine before, don’t change the alignment!
  4. Now the pump should be completely free of hindrances and ready for the three bolts holding it onto the engine block.
    1. Two of the bolts use crescent wrenches, and one uses an allen wrench. The allen bolt was hard to get to and requires much swearing and creative tool usage. I used needle-nosed pliers, an L-shaped standard allen key and then stepped down to the metric allen once it was loose to speed up removal. The bottom bolt was easy. The bolt on the upper-port side was impossible until I bought a new crescent wrench with an off-set head angle.
  5. Note when pulling the pump, you will need to replace the mating surface gasket.
  6. It took quite a bit of turning and angling to get the pump out, but she was finally free!
  7. Now clean the mating surfaces to remove the old gasket. I used a paint scraper and acetone. Careful not to get anything inside the gearing. I took a photo with my phone to see in and was glad I did. Some of the old gasket had fallen in there!
  8. I dropped my pump off at Precision Fuel Injection just down the road in Honolulu to get refurbished. They were recommended by my fellow slip neighbors and Ed was really helpful. He answered a lot of my questions and had some good recommendations on future trouble-shooting techniques. The pump was finished a few days later with some new parts, a good cleaning and a successful bench test. Total cost for refurbishing and bench testing: $585.
    Ouch.
  9. Replacing the injector pump.
    1. Replacing the pump was just as hard as removing it, but in reverse. Don’t forget to put in new gaskets:
      1. I used a thin paper gasket cut from a sheet of gasket material from Napa for the injector pump.
      2. And I used the same material to cut gaskets for the exhaust manifold.
    2. Oh, and one more tip for reassembly: Make sure you don’t skip a step in reverse and be sure everything is tight as you go. If you forget to finish tightening that one fuel hose fitting and it leaks when starting the engine, you will have to tear everything apart again to get to it! Talk about frustrating! (Yes, that happened to me. Doh!)

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