TURBO PARTS Technical Information Brochure www.hoffer-products.com
TURBO introduction As the number of modern turbo diesel vehicles in circulation grows and manufacturers turn into small turbocharged gasoline engines, the so-called DOWNSIZING, the use of TURBO is more and more frequent. As the cost to replace a damaged turbocharger is rather significant, its repair seems a more reasonable choice. Hoffer offers professionals the best solution available through a new range of products including quality TURBO parts such as Core Assy (Turbo Cartridges), Variable Geometry Nozzle KITS and Turbo gasket Kits. Now available… www.hoffer-products.com
Core Assy The Core Assy is the heart of the turbocharger and it consists of: � the turbine’s impeller � the compressor’s impeller � the center housing/hub The center housing surrounds the shaft and the bearings. Oil from the engine or coolant (in case of a water cooled turbocharger) passes through it. In the company’s range one can find the corresponding CORE ASSY for most modern applications, for both diesel and gasoline engines. Our Turbo Parts Catalogue is now available in PDF. www.hoffer-products.com
Variable Geometry Turbo (VNT) The variable geometry nozzles are used to maintain the turbocharger’s efficiency at the highest possible rate for the entire engine’s operating range. Mainly, the variable geometry turbo is used in the modern turbo diesel engines. Turbocharged gasoline engines are not equipped with a VNT ΚΙΤ variable geometry turbo (with some exceptions, like the 997 Porsche turbo). The conventional materials that are used cannot withstand the excessively high temperatures of a gasoline engine exhaust gases whereas they can cope with the lower temperature of diesel engines exhaust gases. 1) Low rpm - closed vanes 2) High rpm - open vanes 1 2 VNT ΚIT available by HOFFER � Each ΚΙΤ contains the mechanism, the vanes and the appropriate screws and rings. Gasket sets for turbocharger repair… Gasket sets like the one illustrated, contain exhaust manifold gaskets, turbine gasket and oil tube gaskets. 60703 www.hoffer-products.com
Turbo problems and their causes Foreign objects Foreign objects that may enter the air induction system or the exhaust system can reach the turbine and damage the impeller and the VNT vanes. Lack of lubrication Poor quality lubricants, false gasket installation and blocking of the oil tube, are the main reasons for excessive wear or failure of the shaft and bearings. By switching the engine off right after a rapid acceleration, we interrupt the oil flow to the turbocharger, while the shaft still rotates at high speed. This practice can cause excessive wear to the shaft and bearings. Oil contamination The accumulation of carbon or metal particles in the lubricant, created by poor maintenance of the engine, will cause excessive wear to the turbo’s shaft and bearings. High rotation speed and temperature Rotation of the shaft and turbocharger impellers at high speed and high operating temperatures outside manufacturer specification limits, may cause the destruction of the turbocharger. www.hoffer-products.com
How to identify a turbocharger All turbochargers have a numeric or alphanumeric code, usually on a label or stamped on the compressors housing. The turbo code (red frame in the photo) is all that is needed for the identification. Alternatively, you can use the original code (OE). You can find below some explanatory photos of various types that may be useful for correct identification: www.hoffer-products.com
Core Assy installation instructions Step 1.. Every Core Assy has been manufactured and tested in compliance with the UNI EN ISO 9001 : 2008 standard guidelines and results to be perfectly interchangeable with the original part. The operating conditions of the Core Assy installed on the engine have been carefully simulated during balancing phase, carried out with oil at engine running temperature. What to check before the installation: Before mounting the new Core Assy, you must identify and eliminate the breakdown causes of the previous turbo. CAUTION Non-compliance with these instructions can cause the turbo breaking down and warranty cancellation. STEP 1 BEFORE ASSEMBLING THE TURBOSUPERCHARGER The following equipment inspections and checks for correct conditions and cleaning must be carried out: � Engine intake equipment: air filter, intake duct, mass air flow meter, intake manifold, etc. � Engine delivery equipment: delivery duct, intercooler, EGR recirculation circuit, etc. � Engine exhaust equipment: exhaust manifold, pipes, catalytic converter, muffler, etc. � Quantity and pressure of the turbo inlet oil: minimum pressure: 200 kPa (2 bar); remove any obstruction and liquid gaskets from turbo inlet and outlet. � Oil drain and engine breather pipe: replace and clean the breather filter to avoid counter-pressure build-up. It is also advisable to repeat this frequently during periodic maintenance. www.hoffer-products.com
Core Assy installation instructions Step 2.. STEP 2 CORE ASSY MOUNTING If a Variable-Nozzle Turbine (VNT) mechanism (variable geometry) is present, the following operations must be carried out before passing to STEP 3 (Turbocharger assembling): � Check for structural and dimensional integrity of VNT mobile vanes. If any breaking, crack, bending or deformation is present, this mechanism must be replaced. � Clean carefully the variable geometry mechanism and mount it again, ensuring that a perfect sliding of the VNT mechanism is provided. � Carry out the VNT mechanism adjustment and after it, the pneumatic actuator check. www.hoffer-products.com
Core Assy installation instructions Step 3.. STEP 3 VARIABLE GEOMETRY (VNT) ADJUSTMENT There are two basic VNT mechanism adjustment methods, identify the applicable one and follow its procedure: ADJUSTMENT OF “A-TYPE” VNT MECHANISM � Insert the old body in the exhaust carter well cleaned, ensuring that the variable geometry is correctly mounted. � Send the VNT command lever over the body against the adjustment grub screw. � Lift up vertically the old central body, taking maximum care not to move the VNT mechanism, and measure the distance between a mobile vane and the next one. (for instance: 1,5 mm). � Insert the new Core Assy into its carter seat and set the same value as previously measured between the vanes, by reversing the above procedure steps and screwing the adjustment grub screw of the new Core Assy. www.hoffer-products.com
Core Assy installation instructions Step 3 continue.. ADJUSTMENT OF “B-TYPE” VNT MECHANISM � Ensure that the variable geometry is correctly mounted. � Insert the old body in the exhaust carter well cleaned and fix it by its two locking screws. � Place a centesimal dial gauge on the pin (where the rod of the pneumatic actuator shall be hooked afterwards) of the mobile command lever over the body, parallel to the adjustment grub screw; preload the dial gauge of about 5 mm, and then set it to zero. Unscrew the 8 mm locking nut of the adjustment grub screw, taking maximum care not to move the dial gauge, and completely unscrew the adjustment grub screw. Detect and note the shifting that has taken place by reading the centesimal dial gauge (for instance: its hand has moved of 1,65 mm). � Insert the new Core Assy into the exhaust carter and ensure that unscrewing the adjustment grub screw the vanes reach full closure at “ZERO”, one against the other, or against the rollers, according to the type of employed variable geometry: 11 vanes / 9 vanes. www.hoffer-products.com
Core Assy installation instructions Step 3 continue.. ADJUSTMENT OF “B-TYPE” VNT MECHANISM two last tasks… � Once everything has been verified, lock the new Core Assy into its seat in the exhaust carter, unscrew the adjustment grub screw, and send the command lever to its travel end, towards the adjustment grub screw. � Place again the centesimal dial gauge and, by screwing the adjustment grub screw, set the same value as previously measured between the vanes by the dial gauge reading. PNEUMATIC ACTUATOR CHECK Once the variable geometry has been properly adjusted, check the pneumatic actuator. - Check that the intake carter, is well cleaned and free from any depot material due to previous rubbings, place it in position and tighten its fixing screws. - Ensure that the turbine shaft and its compression rotor can turn freely without any rubbing or obstacle. www.hoffer-products.com
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