New Product Information - LF1
The purpose of New Product Information is to highlight or indicate important changes from the previous model year.
Changes may include one or more of the following items:
| • | Torque values and/or fastener tightening strategies |
| • | Changed engine specifications |
| • | New sealants and/or adhesives |
| • | Disassembly and assembly procedure revisions |
| • | Engine mechanical diagnostic procedure revisions |
| • | New special tools required |
| • | A component comparison from the previous year |
Torque Values and/or Fastener Tightening Strategies
| • | All fasteners and threaded holes on the engine utilise metric thread. |
| • | Cylinder head, front cover, and crankshaft main bearing cap bolts now apply a two-step, torque and angle tightening strategy. |
| • | Certain fasteners may not be used again. Bolts, studs, or other fasteners that must be replaced will be called out in the specific service procedure. |
| • | There are high strength stainless steel fuel lines that require extreme care and proper order and torque when tightening the connections. Refer to specific service procedures for details. |
Changed Engine Specifications
A variety of specifications have been revised based on the new design LF1 engine. Refer to
Engine Mechanical Specifications : LF1 .
New Sealants and/or Adhesives
Sealants and adhesives, as required, are identified within the specific service procedures. Refer to Adhesives, Fluids, Lubricants, and Sealers .
Disassembly and Assembly Procedure Revisions
A variety of procedures have been revised based on the new design of the LF1 engine. Particular areas of note are:
| • | New-design SIDI fuel system. |
| • | New cylinder heads with integrated exhaust manifold. |
| • | New pistons, rings, and connecting rods. |
| • | Two distinct inlet manifolds; one FWD, one RWD. |
| • | Unique PCV systems in some vehicles. |
| • | Structural front cover, shared with other HFV6 applications. |
| • | Single belt accessory drive, shared with other HFV6 applications. |
| • | Plastic thrust rings installed between cam position actuators and camshafts, shared with other HFV6 applications. |
Engine Mechanical Diagnostic Procedure Revisions
Diagnosis on a vehicle should follow a logical process. Strategy based diagnostics is a uniform approach for repairing all systems. The diagnostic flow should always be used in order to resolve a system condition. The diagnostic flow is the place to start when repairs are necessary. For a detailed explanation, refer to Diagnostic Starting Point - Vehicle .
New Special Tools Required
| • | EN-49248 Injector Rail Assembly Remover is used to remove the injectors and fuel rail assembly from the cylinder head. The fuel injectors are fastened to the fuel rail itself and do NOT separate from the fuel rail while on the engine. The fuel rail must be removed to separate the injectors from the rail. Pulling all 3 injectors at once from the cylinder head requires the use of EN-49428 to apply a pulling force along the centreline of the injectors to help prevent damaging the injectors and/or cylinder heads. |
| • | EN-49245 Fuel Injector Seal Install/Sizer is used to load the compression seals on the end of the injector tip and then size them to the injector bore. There are 2 seals on each injector; each must be installed and sized separately before installation into the cylinder head. |
| • | The LF1 fuel injectors use strong steel clips to retain them to the fuel rail. This firm connection between the injectors and fuel rail is required to keep the injectors isolated from the fuel rail, via the O-ring, and the cylinder head, via the twin Teflon bore seals, to help eliminate noise from the injector operation. EN-49247 Injector Retaining Clip Installer is used to install new retaining clips on the injector/fuel rails. Proper/complete installation of the retaining clips is essential to fuel system operation. |
| • | EN-47909 Injector Bore and Sleeve Cleaning Kit consists of 2 brushes, a T-handle and over-sized swabs used to clean the injector bore. This tool is not new but is also to be used with the new LF1 fuel system. |
| • | EN-48896 HP Fuel Pump Installation Alignment Gauge is used to eliminate HP fuel pump damage due to incorrect installation. The Gauge is installed to ensure the fuel pump drive lobe is on the base circle before the fuel pump is installed. This helps prevent damage to the fuel pump. The tool was introduced for the LLT but is also used with the LF1. |
A Component Comparison from the Previous Year
The 3.0L VVT Direct Injection LF1 engine is a new engine option and is in many ways similar to the direct-injected LLT. However, there are important differences from the LLT as well, such as the new fuel system. Refer to
Engine Component Description : LF1 or LFW .
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