Nissan Z - ZX 1970-1988 Repair Guide

Timing Belt/Chain and Tensioner

Print

REMOVAL & INSTALLATION



Except VG Engines

See Figures 1, 2 and 3

  1. Before beginning any disassembly procedures, position the No. 1 cylinder at TDC on the compression stroke.
  2.  
  3. Remove the front cover and the rocker arm cover.
  4.  
  5. With the No. 1 cylinder at TDC, the timing marks on the camshaft sprocket and the timing chain should be visible. Mark both of them with paint. Also mark the relationship of the camshaft sprocket to the camshaft. At this point you will see that there are three sets of timing marks and locating holes in the sprocket. They are for making adjustments to compensate for the timing chain stretch.
  6.  

When timing chain adjustment is required, refer to the Timing Chain adjustment procedures in this section for details.

  1. With the timing marks on the cam sprocket clearly marked, locate and mark the timing marks on the crankshaft sprocket. Also mark the chain timing mark.
  2.  
  3. Unbolt the camshaft sprocket and remove the sprocket along with the chain. When removing the chain, hold it where the chain tensioner contacts it. When the chain is removed, the tensioner is going to come apart. Hold on to it and you won't lose any of the parts.
  4.  



Click image to see an enlarged view

Fig. Fig. 1: Use a puller to remove the crankshaft sprocket



Click image to see an enlarged view

Fig. Fig. 2: Timing chain position



Click image to see an enlarged view

Fig. Fig. 3: Install the timing chain tensioner

The crankshaft sprocket can be removed with a puller, if necessary. There is no need to remove the chain guide unless it is being replaced.

  1. To install the timing chain and the camshaft sprocket together, after first positioning the chain over the crankshaft sprocket, perform the following:
    1. Position the sprocket so that the marks made earlier line up (undisturbed engine). The camshaft and the crankshaft keys should both be pointing upward.
    2.  
    3. If a new chain and/or gear is being installed, position the sprocket so that the timing marks on the chain align with the marks on the sprocket (both keys pointing up); the marks are on the right-hand side of the sprockets as you face the engine.
    4.  
    5. When the chain is installed correctly, there will be 42 links between the mating marks of the chain and sprockets (1970-78).
    6.  
    7. The 1979-83 engines have two marked links which align with the marks on the sprockets, as an aid to proper timing.
    8.  
    9. Count the links; this is an important step. If the exact number of links between the timing marks are not correct, the valve timing will be off and the engine will either not run at all or run very badly.
    10.  

  2.  
  3. Install the chain tensioner. Adjust the protrusion of the chain tensioner spindle to zero clearance.
  4.  
  5. To complete the installation, use a new oil seal and reverse removal procedures.
  6.  

VG Engine
1984-87 MODELS

See Figures 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 and 17

  1. Refer to the Timing Belt/Chain Cover and Seal removal and installation procedures in this section, and remove the timing belt covers.
  2.  
  3. Turn the crankshaft so that the No. 1 cylinder is at the TDC of the compression stroke.
  4.  
  5. Using chalk or paint, mark the relationship of the timing belt to the punch marks on the camshaft and the crankshaft sprockets; also, mark the timing belt's direction of rotation.
  6.  



Click image to see an enlarged view

Fig. Fig. 4: Crankshaft pulley timing marks



Click image to see an enlarged view

Fig. Fig. 5: Distributor rotor position



Click image to see an enlarged view

Fig. Fig. 6: Remove the timing belt cover retaining bolts



Click image to see an enlarged view

Fig. Fig. 7: Remove the upper timing belt cover ...



Click image to see an enlarged view

Fig. Fig. 8: ... and the lower timing belt cover



Click image to see an enlarged view

Fig. Fig. 9: Align the marks on the crankshaft and camshaft with the corresponding marks on the rear timing belt cover



Click image to see an enlarged view

Fig. Fig. 10: Close-up of crankshaft alignment marks on the pulley and cover



Click image to see an enlarged view

Fig. Fig. 11: Use an Allen wrench and open end wrench (or socket) to loosen the tensioner pulley



Click image to see an enlarged view

Fig. Fig. 12: Slide the timing belt off the pulleys



Click image to see an enlarged view

Fig. Fig. 13: Disassembled tensioner and spring



Click image to see an enlarged view

Fig. Fig. 14: Installation of tensioner and spring



Click image to see an enlarged view

Fig. Fig. 15: Tightening the tensioner in place



Click image to see an enlarged view

Fig. Fig. 16: Checking timing belt deflection



Click image to see an enlarged view

Fig. Fig. 17: Exploded view of the timing cover and belt assembly

  1. Loosen the timing belt tensioner and return spring, then remove the timing belt.
  2.  

Before installing the timing belt, confirm that the No. 1 cylinder is set at TDC of the compression stroke.

  1. Remove both rocker arm covers and loosen all rocker arm shaft retaining bolts and remove all the spark plugs.
  2.  

The rocker arm shaft bolts MUST be loosened so that the correct belt tension can be obtained.

  1. Install the tensioner and the return spring. Using a hexagon wrench, turn the tensioner clockwise and temporarily tighten the lock nut.
  2.  
  3. Make sure that the timing belt is clean and free from oil or water.
  4.  
  5. When installing the timing belt align the white lines on the belt with the punch mark on the camshaft pulleys and crankshaft pulley. Have the arrow on the timing belt pointing toward the front belt covers.
  6.  
  7. Using a hexagon wrench, loosen the tensioner lock bolt, then slowly turn the tensioner clockwise and counterclockwise 2-3 times.
  8.  

If the coarse tensioner stud has been removed, be sure to apply locking sealer to the threads before installing it.

  1. Tighten the tensioner lock nut to 32-43 ft. lbs. (42-56 Nm), the rocker arm shaft retaining bolts (in 2-3 stages) to 13-16 ft. lbs. (17-21 Nm).
  2.  

Before tightening, be sure to set the camshaft lobe at the position where the lobe is not lifted.

  1. To complete the installation, use new gaskets and reverse the removal procedures.
  2.  

1988 MODELS
  1. Remove the engine under cover.
  2.  
  3. Drain the engine coolant from the radiator.
  4.  


CAUTION
When draining coolant, keep in mind that cats and dogs are attracted to ethylene glycol antifreeze, and could drink any that is left in an uncovered container or in puddles on the ground. This will prove fatal in sufficient quantity. Always drain the coolant into a sealable container. Coolant should be reused unless it is contaminated or several years old.

  1. Remove the radiator fan and shroud.
  2.  
  3. Remove the alternator, power steering and compressor drive belts.
  4.  
  5. Remove the suction pipe bracket and the lower hose from the suction pipe.
  6.  
  7. Remove the spark plugs.
  8.  
  9. Set the No. 1 cylinder at TDC on its compression drive belt and crankshaft pulley.
  10.  
  11. Remove the front upper and lower belt covers.
  12.  
  13. Using chalk or paint, mark the relationship of the timing belt to the punch marks on camshaft and the crankshaft sprockets; also, mark the timing belt's direction of rotation.
  14.  
  15. Loosen the timing belt tensioner nut, turn the tensioner, and remove the timing belt.
  16.  


WARNING
Do not turn the crankshaft and camshaft separately after removing the timing belt or the valves will strike the piston head.

To install:
  1. To install, confirm that the No. 1 cylinder is set at TDC on its compression stroke.
  2.  
  3. Install the tensioner and tensioner spring.
  4.  

If the stud is once removed, apply locking sealant to the threads of the stud before installing.

  1. Swing the tensioner fully clockwise with a hexagon wrench, and temporally tighten the lock nut.
  2.  
  3. Set the timing belt by aligning the white lines on the timing belt with the punch marks on the camshaft and crankshaft sprockets. Point the arrow on the timing belt toward the front belt cover.
  4.  

There are 133 teeth in the timing belt. There should be 40 teeth between the left and right camshaft sprockets, and 43 teeth between the left camshaft sprocket and the crankshaft timing sprocket.

  1. Loosen the tensioner lock nut, keeping the tensioner steady with a hexagon wrench.
  2.  
  3. Swing the tensioner 70 to 80° clockwise with a hexagon wrench, and tighten the lock nut.
  4.  
  5. Install the spark plugs.
  6.  
  7. Turn the crankshaft clockwise 2 or 3 times, then slowly set the No. 1 cylinder at TDC on its compression stroke.
  8.  
  9. Push the middle of the timing belt between the right camshaft sprocket and the tensioner pulley with a force of 22 lbs. (29 Nm)
  10.  
  11. Loosen the tensioner lock nut, keeping the tensioner steady with a hexagon wrench.
  12.  
  13. Place a 0.35mm thick and 13mm wide thickness gauge between the tensioner pulley and the belt.
  14.  
  15. Turn the crankshaft clockwise, and set the thickness gauge as shown. The timing belt will move about 2.5 teeth.
  16.  
  17. Tighten the tensioner lock nut, keeping the tensioner steady with a hexagon wrench.
  18.  
  19. Turn the crankshaft clockwise, and remove the thickness gauge.
  20.  
  21. Turn the crankshaft clockwise 2 or 3 times, then slowly set the No. 1 cylinder at TDC on its compression stroke.
  22.  
  23. Check the timing belt deflection. There should be a 0.5-0.6 in. (13.0-14.5mm) deflection of the belt at the center point between the left and right camshaft sprockets. Readjust if necessary.
  24.  

TIMING CHAIN ADJUSTMENT



Except VG Engines

See Figure 18

When the timing chain stretches excessively, the valve timing will be incorrect. There are three sets of holes and timing marks on the camshaft sprocket which are provided to correct the valve timing.

If the stretch of the chain roller links is excessive, adjust the camshaft sprocket location by transferring the camshaft set position of the camshaft sprocket from the factory position of No. 1 to No. 2 or 3 as follows:

  1. Turn the crankshaft until the No. 1 cylinder is at TDC of the compression stroke. Check to see if the camshaft sprocket locating notch is to the left of the oblong groove on the camshaft retaining plate.
  2.  



Click image to see an enlarged view

Fig. Fig. 18: Camshaft sprocket adjustment locations

If the notch is to the left of the groove in the retaining plate, then the chain is stretched and needs to be adjusted.

  1. Remove the camshaft sprocket together with the chain and install the sprocket and chain with the locating dowel on the camshaft inserted into either of the other two holes in the sprocket. Use the No. 2 or No. 3 hole, depending on how badly the chain is stretched.
  2.  

If the chain stretch could be corrected by moving the sprocket to the No. 2 position, then the locating dowel on the camshaft would be inserted into the No. 2 hole of the sprocket and the timing mark on the chain would be aligned with the No. 2 mark on the sprocket. The amount of modification for each location is 4° of crankshaft rotation.

  1. Recheck the valve timing as outlined in Step 1 of this procedure. The notch in the sprocket should be to the right of the groove in the camshaft retaining plate.
  2.  
  3. If or when the notch cannot be brought to the right of the groove with the sprocket installed in the No. 3 hole, the timing chain must be replaced to gain the proper valve timing.
  4.  

 
label.common.footer.alt.autozoneLogo