Nissan Maxima 1993-1998 Repair Guide

Valve Lash

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Maximas with VG30E and VE30DE engines use hydraulic type camshaft followers which are not adjustable. If the engine exhibits excessive valve noise, this may indicate valve train wear or clogged camshaft adjusters. These procedures apply only to the VQ30DE engines.

Check and adjust the valve clearances while the engine is cold and not running.

CHECKING



See Figures 1, 2, 3, 4 and 5

  1. Remove the intake manifold collector.
  2.  
  3. Remove the left and right rocker covers.
  4.  
  5. Remove the spark plugs.
  6.  
  7. Set the No. 1 cylinder at TDC on its compression stroke. Align the pointer with the TDC mark on the crankshaft pulley. Check that the valve lifters on the No. 1 cylinder are loose and valve lifters on the No. 4 cylinder are tight. If not, turn the crankshaft one revolution (360 degrees) and align the pointer with the TDC mark on the crankshaft pulley.
  8.  



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Fig. Fig. 1: Align the timing marks to put the number 1 cylinder at TDC on the compression stroke

  1. Check the following valves:
  2.  



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Fig. Fig. 2: First set of valves in position for adjustment. The number 1 cylinder should be at TDC on the compression stroke

    1. Both No. 1 intake valves.
    2.  
    3. Both No. 2 exhaust valves.
    4.  
    5. Both No. 3 exhaust valves.
    6.  
    7. Both No. 6 intake valves.
    8.  


  1. Using a feeler gauge, measure the clearance between the cam follower and the camshaft. Intake valve clearance (cold) is 0.010-0.013 in. (0.26-0.34mm) and exhaust valve clearance (cold) is 0.011-0.015 in. (0.29-0.37mm). The feeler gauge should fit between the cam lobe and the cam follower with slight resistance. If the clearance is excessive, (or too little) select a thicker or thinner gauge until it fits appropriately, and then record the gauge thickness. It may be helpful to draw a diagram of each cylinder to keep track of your measurements.
  2.  



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Fig. Fig. 3: Using a feeler gauge to check the clearance between the cam and the cam follower

  1. Turn the crankshaft 240 degrees and set the No. 3 cylinder to TDC of its compression stroke.
  2.  
  3. Check the following valves:
  4.  



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Fig. Fig. 4: Second set of valves in position for adjustment. The number 3 cylinder should be at TDC on the compression stroke

    1. Both No. 2 intake valves.
    2.  
    3. Both No. 3 exhaust valves.
    4.  
    5. Both No. 4 exhaust valves.
    6.  
    7. Both No. 5 intake valves.
    8.  


  1. Using a feeler gauge, measure the clearance between the cam follower and the camshaft.
  2.  
  3. Turn the crankshaft 240 degrees and set the No. 5 cylinder to TDC of its compression stroke.
  4.  
  5. Check the following valves:
  6.  



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Fig. Fig. 5: Third set of valves in position for adjustment. The number 5 cylinder should be at TDC on the compression stroke

    1. Both No. 1 intake valves.
    2.  
    3. Both No. 4 exhaust valves.
    4.  
    5. Both No. 5 exhaust valves.
    6.  
    7. Both No. 6 intake valves.
    8.  


  1. Using a feeler gauge, measure the clearance between the cam follower and the camshaft.
  2.  
  3. If all the valve clearances are within specification, install the cylinder head covers, spark plugs, and the intake manifold collector.
  4.  

ADJUSTING



See Figures 6, 7, 8 and 9

If an adjustment is necessary, the valve clearance can be changed by replacing the shim(s). Valve adjustment will require special tool set, Nissan No. KV101151S0 The Camshaft Pliers will allow you to grip the camshaft and depress the cam follower. The Cam Follower Keeper allows the cam follower to remain depressed when the pliers are removed. These specialized tools are also made by aftermarket manufacturers and are usually available at most auto parts stores.



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Fig. Fig. 6: These special tools, available from Nissan or the aftermarket, will be required to adjust the valves

  1. Turn the crankshaft CLOCKWISE so the camshaft lobe of the valve to be adjusted is pointed straight up.
  2.  
  3. Turn the cam follower so the notch is pointed towards the center of the cylinder head; this will facilitate the shim removal process.
  4.  
  5. Using the camshaft pliers, (tool No. KV10115110 or equivalent), push down on the cam follower and insert the cam follower keeper (tool No. KV10115120 or equivalent) on the edge of the cam follower to keep it in the depressed position.
  6.  



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Fig. Fig. 7: Insert the keeper tool between the camshaft and the cam follower while pushing down with the pliers


CAUTION
Be sure keeper tool is fully seated on the edge of the cam follower before removing the camshaft pliers. The keeper tool could slip off the cam follower from the valve spring pressure and become a projectile. Wear safety glasses during this procedure.

  1. Remove the depressor tool and remove the shim with a magnet.
  2.  

Compressed air can be blown into the hole of the cam follower to remove the adjusting shim.

  1. Determine the replacement adjusting shim size by using the following procedures and formula:
  2.  



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Fig. Fig. 8: Use a micrometer to measure the thickness of the shim if the number is worn off



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Fig. Fig. 9: Shim thickness is printed on one side; this side should be face down when installed in the cam follower

    1. Using a micrometer, determine thickness of the removed shim.
    2.  
    3. Calculate the thickness of a new adjusting shim so valve clearance is within the specified values.

      Intake shim determination formula: N = R + (M - 0.0118 in. or 0.30mm)
       
      Exhaust shim determination formula: N = R + (M - 0.0130 in. or 0.33mm)
       
      R = thickness of the removed shim.
       
      N = thickness of the new shim.
       
      M = measured valve clearance.
       

    4.  
    5. Shims are available in 64 sizes from 0.0913-0.1161 in. (2.32-2.95mm) in steps of 0.004 in. (0.01mm). The thickness is stamped on the shim; this side is always installed facing down. Select new shims with thickness as close as possible to calculated value.
    6.  


  1. Install the new shim, then depress the cam follower with the camshaft pliers and remove the keeper tool. Check the valve clearance. Repeat this procedure for any other valves requiring adjustment.
  2.  

 
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