Fitting pistons (in situ)
 
  
 
 
  
   
    
     |  | Fitting pistons (in situ) | 
   
  
  
   
   
   
   
    (Cylinder head removed)
    
    
    
      
    
    
   
   
  
   
    
     
      | Important | 
     
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        Pistons of different makes must not be used in the same engine. The name of the manufacturer is cast inside the piston.
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      | 1. | Assemble piston and connecting rod by driving in the gudgeon pin, using a plastic mallet and drift. Make sure that the mark on the piston crown faces the timing cover and that the numbers on the connecting rods face the exhaust side. 
 
 
         
          
           | Important |  
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             If one connecting rod is to be changed to a newer type (part no. 91 97 617), all the connecting rods must be changed or the difference in weight will become too great.
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      | 2. | Fit the gudgeon pin lock ring. 
 
 
         
          
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                   |  Warning |  
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                         It is extremely important to fit the lock ring with its opening upwards.
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      | 3. | Place the bearing halves in place in the connecting rods. 
 
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      | 4. | Fit protective sleeves, part no. 75 19 531, on the connecting rod studs and oil the piston rings, bearings and cylinder. 
 
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      | 5. | Fit the piston using the fitting tool, part no. 78 62 287. 
 
   
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      | 6. | Fit the big-end bearing caps with bearing halves (connecting rod numbers facing in the same direction). 
 Tightening torques:
 
 20 Nm + 70˚ (14.8 lbf ft + 70˚)
 
 
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      | 7. | Check that there are no impurities or other foreign matter in the sump and clean the sealing surfaces with benzine. 
 
   
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      | 8. | Apply an even bead of flange sealant, part no. 93 21 795, to the sealing surface of the oil sump and fit the oil sump. 
 Tightening torque: 22 Nm (16.2 lbf ft)
 
 
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      | 9. | Fit the protective plate. 
 
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      | 10. | Lift up the subframe and bolt it in place. 
 
   Tightening torques:
 
 Front: 115 Nm (85 lbf ft)
 
 Centre: 190 Nm (140.6 lbf ft)
 
 Rear: 110 Nm + 75˚ (81.4 lbf ft + 75˚)
 
 
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      | 11. | Fit and tighten the end piece nuts. 
 Tightening torque: 75 Nm (55.5 lbf ft)
 
 
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      | 12. | Clean the area for the joint in the exhaust pipe. 
 
   
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      | 13. | Fit the front exhaust pipe. Lubricate the stud on the turbocharger with Molycote 1000 before fitting. 
 
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      | 14. | Screw together the joint between the front and intermediate exhaust pipes. 
 
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      | 15. | Fit the air shields and wheels. 
 Tightening torques:
 
 Wheels: 120 Nm (89 lbf ft)
 
 
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      | 16. | Make sure the oil drain plug is tight, lower the car and fill with engine oil. Replace the dipstick, connect the oxygen sensor cable and remove the lifting beam 
 
   
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