Discussion: NBS Injector Swap How to

Discussion in 'Performance' started by bgray, Mar 29, 2012.

  1. bgray

    bgray Stylish Canadian

    Messages:
    3,102
    Write up For Swappign Injectors on a NBS. Most common swap for MArine inejctors for running heads and cam, or big cam
    Tools
    Small screw driver
    Torx Bits
    10mm Socket

    Supplies
    Sythetic Lube

    First, You need to remvoe the engine cover, and unplug all of the Injector Wires. Remeber to disconnect your battery, I like to use quick disconnects like this that save your radio settings, but un ground the battery...


    Here are my new 31-32 lb inejctors. Out of a 8.1L truck, bolt right up. Even the 42# marines looks about the same. Come with new orings

    [​IMG]

    To disconnect the harnass from each injector you simply need to remove the grey palstic locks that run length wise, and then depress a small black tab to unlock the clip and pull off injector...

    Your next step is to Release all of the system pressure that is built up in the lines. On the Pass. side there is a small air valve and cap..unscrew the cap, and use a small screw driver, with a rag underneath, to relase pressure from the FI system. Careful, full will spray, I recommend a good size rag and safety glasses for sure...

    [​IMG]

    On the Passenger side Make sure to disconnect the Vaccum for the Fuel Pressure Regulator

    [​IMG]

    On the Main fuel rails on both sides are other fuel lines that conenct in. One on both passenger(one Tube) and driver(2 tubes) sides. Using a small Torx Bit, Unscrew the hold down plates, and pull the tubes out...again fuel will come out, and becareful to not lose the orings.
    driver Side
    [​IMG]
    [​IMG]

    Pass Side
    [​IMG]


    On the Driver side there is a bracket that must be removed that bolts under the fuel rail hold down...this bracket supports the two other driver side fuel lines...
    [​IMG]


    Remove the Fuel Rail 10mm screws on both side..Again..there is fuel in the rails...just be careful

    [​IMG]
    [​IMG]

    Now that the rails are out, Remove the small metal clips on the bottom of the injectors where they are attahced to the fuel rail and remove all 8 injectors. I used a twisting and upward motion to remove them...mind the orings etc


    [​IMG]

    To install the new inejctors, take a small amount of lube and lube ONLY THE ORING...be very careful do not get anywhere near the spray outputs...then simply push the inejctors into the rails

    [​IMG]
    [​IMG]


    Reisntall the metal clips

    Now reinstall everything....make sure the injectors are seated properly into the motor, and reattached fuel rail brackets and 10mm screws, vaccum line, plug in injectors, put on clip lock and tie up all other lose ends.

    The truck will need a tune to run properly..i dont suggest running the car due to a risk of Fuel Washing the cylinders...ITR is 28.0 for my cam and tune
     
    Last edited: Mar 29, 2012
  2. Jrluz14

    Jrluz14 New Member

    Messages:
    356
    Sticky this right MEOW!
     
  3. Oktain

    Oktain Canuck Admin Staff Member

    Messages:
    4,916
    Fix your pics Brandon, then I will stick this.

    :shake:
     
  4. bgray

    bgray Stylish Canadian

    Messages:
    3,102
    Should be good now, I got the thermostat one done too.
     
  5. Jrluz14

    Jrluz14 New Member

    Messages:
    356
    We need more stickies like this. Is the search any better on here?
     
  6. Blitzbody37

    Blitzbody37 New Member

    Messages:
    39
    after you swap the injectors, do you just turn on the truck to get the fuel pressure back up? i need to replace just one of mine. thanks
     
  7. Mike

    Mike Banned from GMFS

    Messages:
    420
    The search will function a millions times better here.because there is less bullshit threads to clump things up
     
  8. bgray

    bgray Stylish Canadian

    Messages:
    3,102

    Yes once you button it back up, cycle the keys a few times, release pressure(and air) in the rail again, then cycle the key a few times more and it'll start
     
  9. Adjusted

    Adjusted Super Moderator

    Messages:
    3,623
    Nice write up, looks like you nailed it. How much are the 8.1l injectors?
     
  10. Blitzbody37

    Blitzbody37 New Member

    Messages:
    39
    thanks man
     
  11. bgray

    bgray Stylish Canadian

    Messages:
    3,102
    Believe i paid about 450 for my set for my lq9, don't quote me on it tho
     
  12. Jared

    Jared Administrator Staff Member

    Messages:
    20,614
    good god this is great, BRANDON, you ready?
     

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