Nissan Z - ZX 1970-1988 Repair Guide

Camshaft And Bearings

Print

REMOVAL & INSTALLATION



Except VG Engines
  1. Refer to the Cylinder Head removal and installation procedures in this section, and remove the cylinder head.
  2.  
  3. To remove the valve rocker arms, perform the following:
    1. Remove the valve rocker spring.
    2.  
    3. Loosen the rocker arm pivot locknut; loosen the adjustment as far as possible. Using a medium prybar, depress the valve spring and remove the rocker arm.
    4.  

  4.  
  5. Remove the camshaft locating plate.
  6.  
  7. Pull the camshaft slowly out toward the rear of the head, being especially careful to avoid damaging the lobes and bearings.
  8.  
  9. To install the camshaft, perform the following:
    1. Coat the camshaft bearings and the cam lobes with clean motor oil. Carefully slide the camshaft in place in the camshaft carrier.
    2.  
    3. Install the camshaft locating plate with the groove in the upward position.
    4.  

  10.  
  11. To complete the installation, use new gaskets and reverse the removal procedures. Adjust the timing chain (if necessary) and the valve rocker arm pivots.
  12.  

VG Engines

See Figures 1, 2, 3, 4, 5, 6, 7, 8 and 9

  1. Refer to the Cylinder Head removal and installation procedures in this section, and remove the cylinder head.
  2.  
  3. Remove the rocker shafts with the rocker arms; loosen the bolts in two or three stages.
  4.  

Hold the valve lifters with wire so that they will not drop from the lifter guide. Put an identification mark on the lifters to avoid mixing them up.

  1. Remove the hydraulic valve lifters and lifter guide.
  2.  



Click image to see an enlarged view

Fig. Fig. 1: Exploded view of cylinder head and camshaft assembly-1984-88 models



Click image to see an enlarged view

Fig. Fig. 2: Remove the the lower rocker arm and shaft assembly ...



Click image to see an enlarged view

Fig. Fig. 3: ... followed by the upper arm and shaft assembly



Click image to see an enlarged view

Fig. Fig. 4: Prior to removing the lifter assembly, secure each lifter from the top with wire



Click image to see an enlarged view

Fig. Fig. 5: Remove the lifter assembly from the cylinder head



Click image to see an enlarged view

Fig. Fig. 6: Nissan VG engine lifter with oil hole on the side of the lifter



Click image to see an enlarged view

Fig. Fig. 7: Top view of lifter and oil hole



Click image to see an enlarged view

Fig. Fig. 8: Oil hole in cylinder head above camshaft



Click image to see an enlarged view

Fig. Fig. 9: Remove the camshaft in the direction of the arrow

  1. At the rear of the cylinder head, remove the cylinder head rear cover, the camshaft bolt and the locating plate.
  2.  
  3. Remove the camshaft and the camshaft oil seal through the front of the cylinder head.
  4.  
  5. Using a putty knife, clean the gasket mounting surfaces.
  6.  
  7. To install the camshaft, perform the following:
    1. Install the camshaft.
    2.  
    3. Apply engine oil to the camshaft oil seal and install it in place.
    4.  
    5. Adjust the camshaft end-play with the correct locating plate.
    6.  

  8.  
  9. Install the camshaft pulleys.
  10.  

The right and left camshaft pulleys are different parts. Install them in their correct positions. The right pulley has an R3 identification mark and the left one has an L3.

  1. To complete the installation, use new gaskets and an oil seal, and reverse the removal procedures. Refer to the timing belt procedure, and adjust the timing belt. Refill the cooling system.
  2.  

INSPECTION



Camshaft End-Play

See Figures 10, 11 and 12

Using a dial indicator, measure the camshaft end-play. If the camshaft end-play exceeds the limit of 0.003-0.01 in. (0.08-0.40mm) (except VG) or 0.001-0.002 in. (0.03-0.06mm) (VG), perform the following:

  1. On all engines except VG, replace the thrust plate.
  2.  
  3. On the VG engine, select the thickness of a cam locating plate that will bring the end-play within specifications.
  4.  



Click image to see an enlarged view

Fig. Fig. 10: Use a dial indicator to measure end-play



Click image to see an enlarged view

Fig. Fig. 11: Select shim thickness such that camshaft end-play is within specification



Click image to see an enlarged view

Fig. Fig. 12: Install a cam locating plate which maintains the proper end-play of each camshaft

Example:

If camshaft end-play measures 0.003 in. (0.08mm) with shim 2 used, then change shim 2 to shim 3 so that the camshaft end-play is 0.002 in. (0.05mm).

Camshaft Journal Clearance

See Figure 13

Using an internal dial indicator, measure the inside diameter of the camshaft bearings in the head; using a micrometer, measure the diameter of the camshaft journals.



Click image to see an enlarged view

Fig. Fig. 13: Determining camshaft journal clearance

Standard Inside Diameter:



1.872-1.8726 in. (48.000-48.016mm), for all engines-except VG.
 



1.83-1.834 in. (47.000-47.025mm), for VG engines.
 

Standard Outside Diameter:



1.87-1.8705 in. (47.949-47.962mm), for all engines-except VG engines.
 



1.83-1.831 in. (46.940-46.960mm), for VG engines.
 



Wear limit: 0.006 in. (0.15mm).
 

Camshaft Run-Out

See Figure 14

  1. Place the camshaft (using the camshaft journals) onto a set of V-blocks.
  2.  
  3. Using a dial indicator, place it so that it rides on the camshaft journal.
  4.  
  5. Turn the camshaft and measure the run-out of the camshaft journals.
  6.  



Click image to see an enlarged view

Fig. Fig. 14: Checking the camshaft run-out

  1. The maximum run-out is 0.1mm.
  2.  

 
label.common.footer.alt.autozoneLogo