Nissan Stanza/200SX/240SX 1982-1992 Repair Guide

Camshaft and Bearings

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Since these engines do not use replaceable camshaft bearings, overhaul is performed by replacement of the camshaft or the cylinder head. Check the camshaft bearing surfaces (in the cylinder head) with an internal micrometer and the bearing surfaces (of the camshaft) with a micrometer.

REMOVAL & INSTALLATION



200SX (Z Series Engine)

See Figures 1, 2, 3 and 4



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Fig. Fig. 1: Thickness gauge in correct position for proper adjustment



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Fig. Fig. 2: Check timing belt deflection - 1988 200SX VG30E engine



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Fig. Fig. 3: Timing mark alignment - Stanza CA20 engine



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Fig. Fig. 4: Rocker shaft assembly - Z series engine

Removal of the cylinder head from the engine is optional. Mark and keep all parts in order for correct installation.

  1. Remove the camshaft sprocket from the camshaft together with the timing chain, after setting the No. 1 piston at TDC on its compression stroke. Refer to the Timing Chain Removal and Installation procedures.
  2.  
  3. Loosen the bolts holding the rocker shaft assembly in place and remove the six center bolts. Do not pull the four end bolts out of the rocker assembly because they hold the unit together.
  4.  

When loosening the bolts, work from the ends in and loosen all of the bolts a little at a time so that you do not strain the camshaft or the rocker assembly.

  1. After removing the rocker assembly, remove the camshaft. Slide the camshaft carefully out of the front of the vehicle.
  2.  

Mark and keep the disassembled parts in order.

If you disassembled the rocker unit, assemble as follows.

  1. Install the mounting brackets, valve rockers and springs observing the following considerations:
    1. The two rocker shafts are different. Both have punch marks in the ends that face the front of the engine. The rocker shaft that goes on the side of the intake manifold has two slits in its end just below the punch mark. The exhaust side rocker shaft does not have slits.
    2.  
    3. The rocker arms for the intake and exhaust valves are interchangeable between cylinders one and three and are identified by the mark 1. Similarly, the rockers for cylinders two and four are interchangeable and are identified by the mark 2.
    4.  
    5. The rocker shaft mounting brackets are also coded for correct placement with either an A or a Z plus a number code. See the illustration for proper placement.
    6.  

  2.  
  3. Check camshaft run-out, end-play wear and journal clearance as described in this section.
  4.  

To install:
  1. Apply sealant to the end camshaft saddles as shown in the accompanying illustration. Place the camshaft on the head with its dowel pin pointing up.
  2.  
  3. Fit the rocker assembly on the head, making sure you mount it on its knock pin.
  4.  
  5. Torque the bolts to 11-18 ft. lbs., in several stages working from the middle bolts and moving outwards on both sides.
  6.  

Make sure the engine is on TDC of the compression stroke for No. 1 piston or you may damage some valves.

  1. Adjust the valves. Refer to the Valve Adjustment procedure.
  2.  

200SX and Stanza (CA Series Engine)

See Figures 5, 6 and 7



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Fig. Fig. 5: Note the difference in rocker shafts - Z series engine



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Fig. Fig. 6: Rocker shaft mounting brackets are assembled in this order - Z series engine



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Fig. Fig. 7: Apply sealant to these points on the cylinder head just before installing the camshaft - Z series engine

  1. Disconnect the negative battery cable and relieve the fuel system pressure if necessary.
  2.  
  3. Set the No. 1 piston to TDC of the compression stroke.
  4.  
  5. Remove the timing belt.
  6.  
  7. Remove the valve rocker cover.
  8.  
  9. Fully loosen all rocker arm adjusting screws (the valve adjusting screws). Loosen the rocker shaft mounting bolts in 23 stages and then remove the rocker shafts as an assembly. Keep all components in the correct order for reassembly.
  10.  
  11. Hold the camshaft pulley and remove the pulley mounting bolt. Remove the pulley. Remove the camshaft thrust plate.
  12.  
  13. Carefully pry the camshaft oil seal out of the front of the cylinder head.
  14.  
  15. Slide the camshaft out the front of the cylinder head, taking extreme care not to score any of the journals.
  16.  

To install:
  1. Coat the camshaft with clean engine oil.
  2.  
  3. Carefully slide the camshaft into the cylinder head, coat the end with oil and install a new oil seal. Install the camshaft thrust plate and wedge the camshaft with a small wooden block inserted between one of the cams and the cylinder head. Torque the thrust plate bolt to 5865 ft. lbs. (7888 Nm). Remove the wooden block.
  4.  
  5. Lubricate the rocker shafts lightly with clean engine oil and install them, with the rocker arms, into the head. Both shafts have punch marks on their leading edges, while the intake shaft is also marked with 2 slits on its leading edge.
  6.  

To prevent the rocker shaft springs from slipping out of the shaft, insert the bracket bolts into the shaft prior to installation.

  1. Tighten the rocker shaft bolts gradually, in 23 stages (from the center of the shaft to the end of the shaft assembly) to 1316 ft. lbs. (1822 Nm).
  2.  
  3. Install the camshaft pulley and then install the timing belt.
  4.  
  5. Adjust the valves as required and install the cylinder head cover.
  6.  
  7. Connect the negative battery cable.
  8.  

200SX (VG30E Engine)

See Figures 8, 9, 10, 11, 12 and 13

On the 1987 200SX with VG30E engine Nissan recommends that the engine assembly be removed from the vehicle, then the cylinder heads disassembled. On the 1988 200SX with VG30E engine Nissan recommends that the cylinder heads be removed from the engine, with the engine mounted in the vehicle, and then remove the camshafts. This procedure is for removing the camshafts with the engine in the vehicle.

  1. Disconnect the negative battery cable.
  2.  
  3. Drain the cooling system.
  4.  
  5. Remove the timing belt.
  6.  
  7. Remove the collector assembly.
  8.  
  9. Remove the intake manifold.
  10.  
  11. Remove the cylinder head.
  12.  
  13. Remove the rocker shafts with rocker arms. Bolts should be loosened in several steps in the proper sequence (from the end to the center of the shaft assembly).
  14.  
  15. Remove hydraulic valve lifters and lifter guide. Hold hydraulic valve lifters with wire so they will not drop from lifter guide.
  16.  
  17. Using a dial gauge measure the camshaft end-play. If the camshaft end-play exceeds the limit _ 0.00120.0024 in. (0.0300.060mm), select the thickness of a cam locate plate so the end-play is within specification. For example, if camshaft end play measures 0.0031 in. (0.08mm) with shim 2 used, then change shim 2 to shim 3 so the camshaft end play is 0.0020 in. (0.05mm).
  18.  
  19. Remove the camshaft front oil seal and slide camshaft out the front of the cylinder head assembly.
  20.  

To install:
  1. Install camshaft, locator plates, cylinder head rear cover and front oil seal. Set camshaft knock pin at 12 o'clock position. Install cylinder head with new gasket to engine.
  2.  
  3. Install valve lifter guide assembly. Assemble valve lifters in their original position. After installing them in the correct location remove the wire holding them in lifter guide.
  4.  
  5. Install rocker shafts in correct position (see illustration) with rocker arms. Tighten bolts in 23 stages (from the center to the end of the shaft assembly) to 1316 ft. lbs. (1822 Nm). Before tightening, be sure to set camshaft lobe at the position where lobe is not lifted or the valve closed. Set each cylinder 1 at a time or follow the procedure below. The cylinder head, intake manifold, collector and timing belt must be installed:
    1. Set No. 1 piston at TDC of the compression stroke and tighten rocker shaft bolts for No. 2, No. 4 and No. 6 cylinders.
    2.  
    3. Set No. 4 piston at TDC of the compression stroke and tighten rocker shaft bolts for No. 1, No. 3 and No. 5 cylinders.
    4.  
    5. Torque specification for the rocker shaft retaining bolts is 1316 ft. lbs. (1822 Nm).
    6.  

  6.  
  7. Fill the cooling system to the proper level.
  8.  
  9. Connect the negative battery cable.
  10.  



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Fig. Fig. 8: Use a sprocket holding tool when loosening the cam sprocket - CA series engine



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Fig. Fig. 9: Note location marks on the end of the shafts, slits on the intake shaft - rocker shaft assembly CA series engine



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Fig. Fig. 10: Rocker shaft assembly removed - CA series engine



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Fig. Fig. 11: Holding the valve lifters in place - 200SX VG30E engine



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Fig. Fig. 12: Select shim thickness so that camshaft thickness is within specifications - 200SX VG30E engine



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Fig. Fig. 13: Using a dial indicator to measure camshaft end-play - 200SX VG30E engine

240SX and 1990-92 Stanza (KA24E Engine)

See Figures 14, 15, 16, 17, 18 and 19



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Fig. Fig. 14: Remove the camshaft in the direction of the arrow - 200SX VG30E engine



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Fig. Fig. 15: Rocker shaft/arm installation - 200SX VG30E engine



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Fig. Fig. 16: Exploded view cylinder head assembly - 200SX VG30E engine



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Fig. Fig. 17: Rocker arm shaft positioning - KA24E engine



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Fig. Fig. 18: Spring clip installation - KA24E engine



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Fig. Fig. 19: Rocker shaft bolt LOOSENING sequence - KA24E engine TIGHTEN IN REVERSE OF THE LOOSENING SEQUENCE

  1. Disconnect the negative battery cable.
  2.  
  3. Remove the timing chain.
  4.  
  5. Remove the cylinder head. Do not remove the camshaft sprocket at this time.
  6.  
  7. Loosen the rocker shaft bolt evenly in proper sequence. Start from the outside and work toward the center.
  8.  
  9. Mount a dial indicator to the cylinder head and set the stylus of the indicator on the head of the camshaft sprocket bolt. Zero the indicator and measure the camshaft end-play by moving the camshaft back and forth. End-play should be within 0.00280.0059 in. (0.070.15mm).
  10.  
  11. Remove the camshaft brackets and lift the camshaft with sprocket from the cylinder head.
  12.  

To install:
  1. Clean all cylinder head, intake and exhaust manifold gasket surfaces. Lubricate the camshaft and rocker arm/shaft assemblies with a liberal coating of clean engine oil. Lay the camshaft and sprocket into the cylinder head so the knock pin is at the front of the head at the 12 o'clock position. Install the camshaft brackets. The camshaft bracket directional arrows must face the toward the front of the engine.
  2.  
  3. Install the rocker shaft and rocker arms. Both intake and exhaust rocker shafts are stamped with an F mark. This mark must face the front of the engine during installation. Install the rocker arm bolts and spring clips so the cut outs are facing as shown. Torque the rocker arm bolts (in several stages) in the proper sequence to 2730 ft. lbs. (3741 Nm).
  4.  
  5. Install the timing chain.
  6.  
  7. Install the cylinder head. Use new rubber plugs when installing the cylinder head.
  8.  
  9. Connect the negative battery cable.
  10.  

240SX (KA24DE Engine)

See Figures 20 and 21



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Fig. Fig. 20: Install camshaft in correct position - KA24E engine



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Fig. Fig. 21: Install camshaft brackets - KA24E engine

Modify service steps as necessary. This is a complete disassembly repair procedure. Review the complete procedure before starting this repair.

  1. Release the fuel system pressure.
  2.  
  3. Disconnect the negative battery cable and drain the cooling system. Drain the engine oil.
  4.  
  5. Remove all vacuum hoses, fuel lines, wires, electrical connections as necessary.
  6.  
  7. Remove the front exhaust pipe and AIV. pipe.
  8.  
  9. Remove the air duct, cooling fan with coupling and radiator shroud.
  10.  
  11. Remove the fuel injector tube assembly with injectors.
  12.  
  13. Disconnect and mark spark plug wires. Remove the spark plugs.
  14.  
  15. Set No. 1 piston at TDC on compression stroke. Remove the rocker cover assembly.
  16.  
  17. Mark and remove the distributor assembly.
  18.  
  19. Remove the cam sprocket, brackets and camshafts. These parts should be reassembled in their original position. Bolts should be loosened in 2 or 3 steps (loosen all bolts in the reverse of the tightening order).
  20.  

To install:
  1. Install camshafts and camshafts brackets. Torque camshaft brackets in two or three steps in sequence. After completing assembly check valve clearance.
  2.  
  3. Install camshaft sprockets.
  4.  
  5. Install chain guide between both camshaft sprockets and distributor assembly.
  6.  
  7. Install all remaining components in reverse order of removal.
  8.  
  9. Connect the negative battery cable. Refill all fluid levels. Road test the vehicle for proper operation.
  10.  

CHECKING CAMSHAFT RUN-OUT



See Figure 22



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Fig. Fig. 22: Exploded view cylinder head assembly - 240SX KA24E engine

Camshaft run-out should be checked when the camshaft has been removed from the cylinder head. An accurate dial indicator is needed for this procedure; engine specialists and most machine shops have this equipment. If you have access to a dial indicator, or can take your cam to someone who does, measure cam bearing journal run-out. The maximum (limit) run-out on the CA20E, CA18ET and KA24E camshafts is 0.02mm. The run-out limit on the Z20 and Z22 series camshafts is 0.20mm. The maximum (limit) run-out on the VG30E camshaft is 0.01mm. If the run-out exceeds the limit replace the camshaft.

CHECKING CAMSHAFT LOBE HEIGHT



See Figures 23 and 24



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Fig. Fig. 23: Camshaft bracket torque sequence - 240SX KA24DE engine



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Fig. Fig. 24: Exploded view cylinder head assembly - 240SX KA24DE engine

Use a micrometer to check cam (lobe) height, making sure the anvil and the spindle of the micrometer are positioned directly on the heel and tip of the cam lobe as shown in the accompanying illustration. Use the specifications in the following chart to determine the lobe wear.

CHECKING CAMSHAFT JOURNALS AND CAMSHAFT BEARING SADDLES



See Figures 25 and 26

While the camshaft is still removed from the cylinder head, the camshaft bearing journals should be measured with a micrometer. Compare the measurements with those listed in the Camshaft Specifications chart in this section. If the measurements are less than the limits listed in the chart, the camshaft will have to be replaced, since the camshafts in all of the engines covered in this guide run directly on the cylinder head surface; no actual bearings or bushings are used, so no oversize bearings or bushings are available.

Using an inside dial gauge or inside micrometer, measure the inside diameter of the camshaft saddles (the camshaft mounts that are either integrally cast as part of the cylinder head, or are a bolted on, one piece unit. The Z-series engines use a saddle-and-cap arrangement. The inside diameter of the saddles on all engines except the CA20E/CA18ET is 48.00-48.01mm. The CA20E/CA18ET measurement is 46.00-46.01mm. The inside diameter on the KA24E with the camshaft bracket and rocker shaft torque to specifications is 31.5-33.00mm. On the VG30E engine contact a Nissan dealer or local machine shop for that specification. The camshaft journal oil clearances are listed in the Camshaft Specifications chart in this section. If the saddle inside diameters exceed those listed above, the cylinder head must be replaced (again, because oversize bearings or bushings are not available).



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Fig. Fig. 25: Check camshaft run-out with a dial indicator



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Fig. Fig. 26: Use a micrometer to check camshaft cam lobe height

CHECKING CAMSHAFT END-PLAY



See Figure 27, 28 and 29

After the camshaft has been installed, end-play should be checked. The camshaft sprocket should not be installed on the cam. Use a dial gauge to check the end-play, by moving the camshaft forward and backward in the cylinder head. End-play specifications for the CA20E, CA18ET, Z20/22 series and KA24E engines should not exceed 0.20mm. On the VG30E engine the camshaft end-play should be between 0.03-0.06mm.



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Fig. Fig. 27: Camshaft specifications



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Fig. Fig. 28: Measuring camshaft journal diameter



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Fig. Fig. 29: Use an inside micrometer or dial indicator gauge to measure camshaft bearing saddle diameters

 
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