FUEL INJECTOR REMOVAL PROCEDURE
Tools required:
EN-47909 Injector Bore Service Kit
J-44639 Injector Removal Tool
Removal Procedure
Important:Refer to Engine Controls Component Views for fuel injector locations. Failure to identify the correct cylinder will result in misdiagnosis.
1. Remove the lower valve cover. Refer to Valve Rocker Arm Cover Replacement - Lower Left Side or Valve Rocker Arm Cover Replacement - Lower Right Side in Engine Mechanical - 6.6L.
Important:When the fuel injector pressure lines are removed, debris may fall into the fuel injector inlet fitting. Remove any debris from the inlet fitting of the fuel injector.
Important:Confirm which side of the banjo washers have the largest outer diameter.
2. Remove the fuel injector return line from fuel injectors.
3. Remove the bolt from the fuel injector bracket.
4. Install J 44639 (2) onto the injector retainer bracket.
5. Install a wrench onto J 44639 (2) and pry away from the fuel injector (1).
6. Remove the fuel injector(s).
7. Remove the copper compression washer from the injector hole if the washer was not removed with the injector.
Fuel Injector Cleaning and Inspection
Important:If reusing the old injectors perform the following:
Notice:The fuel injector must be cleaned with the proper cleaning equipment. DO NOT use abrasive cleaning methods, such as a metallic brush, to remove deposits. Cleaning an injector with improper tools will damage the fuel injector.
1. Use a soft bristle non-metallic brush and top engine cleaner, GMP/N1052626 (Canadian P/N993026) or equivalent, to remove any deposits from the nozzle tip (1) and the copper washer sealing area (2) before re-installation.
2. Inspect the fuel injector nozzle tip (1) for any signs of discoloration (dark yellow, tan, or blue) due to excessive heat.
3. Replace the injector if any damage is found.
4. Clean the fuel injector high pressure line.
5. Inspect the fuel injector high pressure line for excessive corrosion or damage to the sealing surfaces (1, 2). Replace the line if any damage is found.
Injector Bore Cleaning
Important:The procedure below will aid in the cleaning of carbon deposits from the injector sleeve during an injector replacement
1. Install the radial brush (brass) (EN-47909-2), to the handle assembly (EN-47909-1).
2. Insert the brush into the injector bore and rotate the handle in order to break loose any carbon deposits from the injector bore walls and the combustion deck hole.
Caution:Wear safety glasses in order to avoid eye damage.
3. Using compressed air, evacuate any debris from the injector bore.
4. Remove the radial brush from the handle assembly.
5. Install the axial brush (nylon) (EN-47909-3), to the handle assembly (EN-47909-1).
6. Insert the axial brush into the injector bore and rotate the handle while also applying a slight downward pressure, in order to force the brush ends into the bottom corners of the injector bore.
Caution:Wear safety glasses in order to avoid eye damage.
7. Using compressed air, evacuate any debris from the injector bore.
Notice:Do not allow excessive amounts of solvent to go into the cylinder during cleaning. Failure to do so may cause engine damage upon startup.
8. Lightly dampen a cotton swab (EN-47909-20) with GM Top Engine Cleaner, P/N1052626 (CanadianP/N993026) or equivalent, and wipe away any deposits from the injector bore.
Important:DO NOT crank the engine in order to expel any solvent from the cylinder. Cranking the engine with the injector removed may cause the injector sleeve to unseat and fill the cylinder with engine coolant.
9. Inspect the injector bore for any deposits and repeat brushing if necessary.
Installation Procedure
1. If the fuel injector sleeve was pulled from the cylinder head when removing the injector(s), refer to Fuel Injector Nozzle Tube Sleeve Replacement in Engine Mechanical - 6.6L.
2. Install a NEW O-ring onto the fuel injector(s).
3. Lubricate the O-ring with clean engine oil.
4. Install a NEW copper washer into the fuel injector bore in the cylinder head.
5. Install the fuel injector with injector bracket.
Notice:Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.
6. Install the injector bracket bolt.
Tighten
Tighten the bolt to 50N·m (37lbft).
7. Install the return pipe assembly.
8. Install the fuel injector return line to injector eye bolts and washers. Lubricate the washers with diesel fuel prior to installing.
Tighten
Tighten the fuel injector line to injector eye bolts to 16N·m (12lbft).
9. Install the fuel injector return line to cylinder head eye bolts and washers. Lubricate the washers with diesel fuel prior to installing.
Tighten
Tighten the fuel injector return line to cylinder head eye bolts to 17N·m (12lbft).
10. Install the lower valve cover. Refer to Valve Rocker Arm Cover Replacement - Lower Left Side or Valve Rocker Arm Cover Replacement - Lower Right Side in Engine Mechanical - 6.6L.
Fuel injectors may become contaminated during engine servicing. Debris between the injector line and the injector line nut may fall into the injector fuel inlet upon removal. Refer to the following SI procedures for the appropriate model year, vehicle and engine RPO when performing the following bulletin procedures for servicing the fuel injectors and lines.
• / Fuel Injection Fuel Rail Assembly Replacement - Bank 1• / Fuel Injection Fuel Rail Assembly Replacement - Bank 2
• / Fuel Injector Replacement (Right)
• / Fuel Injector Replacement (Left)
Removal of Fuel Injector Lines
1. Before removing the fuel injector line, use regulated compressed air to blow any debris from between the fuel injector line and the fittings (1, 2). Wipe the fittings (1, 2) clean of debris.
2. Spray Super Lube®, P/N12346241 (in Canada, P/N10953474), or a lithium grease equivalent, between the fuel injector line and fittings (1, 2) to assist in containing any debris during removal.
3. Remove the fuel injector line.
4. Remove the upper valve cover.
5. Remove the lower valve cover.
Notice:After the fuel line is removed and the fuel injector inlet is exposed, DO NOT use compressed air to clean debris. Using compressed air can allow debris to enter the fuel injector inlet and damage the fuel injector.
6. Immediately after removal of the lower valve cover, use a vacuum source to remove any contamination in the fuel injector inlet (1).
Fuel Injector Cleaning and Inspection
Notice:The fuel injector must be cleaned with the proper cleaning equipment. DO NOT use abrasive cleaning methods such as a metallic brush to remove deposits. Cleaning an injector with improper tools may damage the fuel injector.
1. Use a soft bristle non-metallic brush and fuel injector cleaner, P/N88861802 (in Canada, P/N88861804), or equivalent, to remove any deposits from the nozzle tip (1) and the copper washer sealing area (2) before reinstallation.
2. Inspect the fuel injector nozzle tip (1) for cracks, dents, or other damage.
3. Inspect the nozzle tip (1) for any signs of discoloration (dark yellow, tan, or blue) due to excessive heat.
Note:For information on injector bore cleaning, refer to Corporate Bulletin Number 05-06-04-067 - Information on New Essential Tool EN-47909 Injector Bore Cleaning Kit for 6.6L Duramax™ Diesel Engine.
⇒ / If any damage is found replace the fuel injector. Clean the fuel injector bore BEFORE installing the new fuel injector.4. Clean the fuel injector high-pressure lines by performing the following steps:
5. Inspect the fuel injector high-pressure line for excessive corrosion, scale or rust to the sealing surface as shown.
Notice: Medium size media glass beads have a cleaning and peening action and do not remove metal. They do not have the quick abrasive action of sharp edged media. Glass beads clean rust, scale and corrosion from metal parts without any damage.
6. Use an Abrasive Blasting Cabinet, P/N624-AST-SBC1, (to order, call GM Dealer Equipment at 1-800-GMTOOLS), or equivalent, with a medium size media glass beads to clean the high pressure lines and fittings.
Important:Black plastic electrical tape or equivalent will protect the fittings outside coating from being removed with the media. This must be done to ALL sixteen high pressure fittings.
7. Install black plastic electrical tape or equivalent on both of the fittings (1) as shown.
8. When using an Abrasive Blasting Cabinet or equivalent, make sure you only clean the inside of the fittings (2) and as much of the fitting threads as possible as shown.
9. Use pipe cleaners (1) to block the ends of the high pressure lines so the abrasive blasting glass beads will not contaminate the inside of the pipes. Before removing the pipe cleaners, clean them by using regulated compressed air to blow any debris and/or media glass beads from the pipe cleaners.
10. There may be some area of the fitting or line that the glass beads did not clean very well. Disregard any surface that did not clean up as long as the area of the fitting is clean at the bite edge or sealing surface. Refer to the above illustration (1). Replace any suspect high pressure line if the glass beads cannot remove corrosion, scale or rust from the sealing surfaces and/or pitting or any other damage that is found.
11. After cleaning all of the fuel injector high-pressure line fittings with the glass beads, clean by using compressed air to blow any debris and/or media glass beads from inside and outside of all the fittings and lines. Afterwards, wash thoroughly with All Purpose Parts Cleaner, P/N88862650 (in Canada, P/N88901247, Brake Parts Cleaner) or equivalent. Repeat this process until all of the debris and/or media glass beads have been removed from the fittings and lines.
Fuel Injector Installation
Install the fuel injectors and lines using published service procedures in SI.
Notice:Ensure proper torquing of the fuel injector line fittings (1, 2). An under-torqued fuel injector line will not seal properly and an over-torqued fuel injector line may damage the fuel injector fitting. An improperly sealed or damaged fuel injector line or fuel injector fitting may cause a fuel leak.
Inspection For Fuel Leaks Into the Engine After Repair
1. Run the engine at idle for 10 minutes. Inspect for external fuel leaks while the engine is running.
2. Stop the engine and wait 10 minutes, then check the engine oil level. This will be the initial oil level.
3. Run the engine at idle for 5 minutes while commanding the fuel pressure to 160MPa using a scan tool.
4. Stop the engine and wait 10 minutes, then check the oil level.
⇒ / If the engine oil level is more than 4.7mm (3/16in) above the initial oil level, refer to Fuel Leak Diagnosis (Inside of Engine), and Fuel in Engine Oil procedures in the Engine Controls and Engine Mechanical sections respectively in SI.5.
⇒ / If the engine oil level is less than 4.7mm (3/16in) above the initial oil level, the repair is complete.