#### TIMING CHAIN ADJUSTMENT

Fig. 1: Timing chain adjustment

When the timing chain stretches excessively, the valve timing will be adversely affected. There are three sets of holes and timing marks on the camshaft sprocket.

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

1. Turn the crankshaft until the No. 1 piston is at TDC on the compression stroke. Examine whether the camshaft sprocket location notch is to the left of the oblong groove on the camshaft retaining plate. If the notch in the sprocket is to the left of the groove in the retaining plate, then the chain is stretched and needs adjusting.
2. Remove the camshaft sprocket together with the chain and reinstall the sprocket and chain with the locating dowel on the camshaft inserted into either the No. 2 or 3 hole of the sprocket. The timing mark on the timing chain must be aligned with the mark on the sprocket. The amount of modification is 4°of crankshaft rotation for each mark.
3. Recheck the valve timing as outlined in Step 1. The notch in the sprocket should be to the right of the groove in the camshaft retaining plate.
4. If and when the notch cannot be brought to the right of the groove, the timing chain is worn beyond repair and must be replaced.

##### 240SX and 1990–92 Stanza (KA24E Engine)

Fig. 2: Timing chain assembly — KA24E engine

Fig. 3: Timing chain and sprocket alignment — KA24E engine

Fig. 4: Correct installation of crankshaft sprocket, oil pump, drive gear, oil thrower — KA24E engine

Fig. 5: Timing chain assembly — KA24E engine

Fig. 6: Oil seals in left side of engine block — KA24E engine

Fig. 7: Installing oil pump — 240SX KA24E engine

Fig. 8: Drive spindle for oil pump in correct location — 240SX KA24E engine

1. Disconnect the negative battery cable.
2. Set the No. 1 piston at TDC of the compression stroke.
3. Remove the front cover.
4. If necessary, define the timing marks with chalk or paint to ensure proper alignment.
5. Hold the camshaft sprocket stationary with a spanner wrench or similar tool and remove the camshaft sprocket bolt.
6. Remove chain tensioner.
7. Remove the chain guides.
8. Remove the timing chain.
9. Remove the sprocket oil slinger, oil pump drive gear and crankshaft gear.

   To install:

10. Install the crankshaft sprocket, oil pump drive gear and oil slinger onto the end of the crankshaft. Make sure the crankshaft sprocket timing marks face toward the front.
11. Install the camshaft sprocket, bolt and washer. The alignment mark must face towards the front. Tighten the bolt just enough to hold the sprocket in place.
12. Verify that the No. 1 piston is at TDC of the compression stroke. The crankshaft key-ways should be at the 12 o'clock position.
13. Install the timing chain by aligning the marks on the chain with the marks on the crankshaft and camshaft sprockets. Torque the camshaft sprocket bolt to 87–116 ft. lbs. (118–157 Nm) once the timing chain is in place and aligned.
14. Install the chain tensioner and chain guide.
15. Install the front cover.
16. Connect the negative battery cable.

##### 240SX (KA24DE Engine)

Fig. 9: Timing chain installation — 240SX KA24DE engine

Fig. 10: Timing chain installation — 240SX KA24DE engine

1. Release the fuel system pressure.
2. Disconnect the negative battery cable and drain the cooling system. Drain engine oil.
3. Remove the cylinder head assembly.
4. Remove the oil pan.
5. Remove the oil strainer, crankshaft pulley.
6. Remove the front cover assembly.
7. Remove the lower timing chain tensioner, tension arm, lower timing chain guide.
8. Remove the lower timing chain and idler sprocket.

   To install:

9. Check all components for wear. Replace as necessary. Clean all mating surfaces and replace the cylinder head gasket.
10. Install crankshaft sprocket. Make sure that mating marks of crankshaft sprocket face front of the engine.
11. Rotate crankshaft so that No. 1 piston is set a TDC position.
12. Install idler sprocket and lower timing chain.
13. Install chain tension arm, chain guide and lower timing chain tensioner.
14. Install front cover assembly.
15. Install crankshaft pulley, oil strainer and oil pan.
16. Install the cylinder head assembly.
17. Install all remaining components in reverse order of removal.
18. Connect the negative battery cable. Refill all fluid levels. Road test the vehicle for proper operation.