REMOVAL & INSTALLATION
See Figures 1, 2, 3, 4 and 5
- If possible, crank the engine around so that the No. 1 cylinder is at TDC on the compression stroke. Remove the distributor cap to confirm and line the timing mark on the damper pulley with "0'' on the timing scale. This will aid in aligning timing marks when installing the timing gears. Disconnect the negative battery cable.
- Drain the cooling system.
- Remove the radiator, fan and all related parts. Remove the water pump.
- Remove the crankshaft pulley.
- Remove the vibration damper using the proper puller.
- Unbolt the chain cover from the block and remove, using caution to avoid damaging the oil pan gasket. Remove the fuel pump from the cover, if equipped.
- Remove the camshaft gear retaining bolt and cup washer. Remove the timing chain and gears. If necessary, remove the chain and upper gear, then use a gear puller to remove the lower gears.
- Place both camshaft and crankshaft gears on the bench with the timing marks on the exact imaginary center line through both gear bores as they are installed on the engine.
- Place the timing chain around both sprockets.
- Turn the crankshaft and camshaft so the keys line up with the keyways in the gears when the timing marks are in proper position.
- Slide both gears over their respective shafts and use a straightedge to check timing mark alignment.
- Install the fuel pump eccentric and cup washer, if equipped. Tighten the camshaft gear retaining bolt to 35 ft. lbs. (47 Nm).
- Clean and dry the mating surfaces of the timing chain cover and block. Apply a thin bead of sealer to the oil pan gasket.
- Install a new cover gasket and install the cover. Tighten the bolts to 30 ft. lbs. (41 Nm).
- Install the water pump with a new gasket, if it was removed.
- Install the damper with tool C-3638, or equivalent, install the bolt and washer and tighten to specification. Apply a small amount of sealer to the bolts and install the crankshaft pulley.
- Install the fuel pump using a new gasket, if equipped and connect the fuel lines. Install the two oil pan bolts if they were removed.
- Install the radiator, fan and all related parts.
- Fill the cooling system.
- Connect the negative battery cable, set all adjustment to specifications and check for leaks.
5.2L and 5.9L Engines
See Figures 5 and 6
- Remove the front cover.
- Remove the camshaft sprocket lockbolt, securing cup washer, and fuel pump eccentric. Remove the timing chain with both sprockets.
- To begin the installation procedure, place the camshaft and crankshaft sprockets on a flat surface with the timing indicators on an imaginary centerline through both sprocket boxes. Place the timing chain around both sprockets. Be sure that the timing marks are in alignment.
- Turn the crankshaft and camshaft to align them with the keyway location in the crankshaft sprocket and the keyway or dowel hole in the camshaft sprocket.
- Lift the sprockets and timing chain while keeping the sprockets tight against the chain in the correct position. Slide both sprockets evenly onto their respective shafts.
- Use a straightedge to measure the alignment of the sprocket timing marks. They must be perfectly aligned.
- Install the fuel pump eccentric, cup washer, and camshaft sprocket lockbolt and tighten to 35 ft. lbs. (47 Nm). If camshaft end-play exceeds 0.010 in. (0.25mm), install a new thrust plate. It should be 0.002-0.006 in. (0.05-0.15mm) with the new plate.
See Figures 7 and 8
- Align the camshaft and crankshaft centerline. Remove the camshaft sprocket attaching bolt and remove the timing chain and camshaft sprockets.
- Use puller No. 6444 and jaws No. 6920, or equivalent, to pull the crankshaft sprocket.
- Align the key in the crankshaft sprocket with the sprocket. Press on the crankshaft sprocket using tools No. C-3688, C-3718 and MB-990799, or their equivalents. Seat the sprocket against the crankshaft shoulder.
- Turn the crankshaft to line up the timing mark with the crankshaft and camshaft centerline.
- Put the timing chain on the camshaft sprocket.
- Align the timing marks and install the chain and camshaft sprocket onto the crankshaft sprocket. Check to see that the timing marks are on the centerline of the crankshaft and camshaft centerline.
- Install the camshaft bolt. Tighten the bolt to 45 ft. lbs. (61 Nm).
- Check the camshaft end-play. If a new thrust plate was installed, the clearance should be 0.002-0.006 in. (0.051-0.152mm). If the used thrust plate is installed, the end-play clearance may be up to 0.010 in. (0.254mm).
- If not within these limits, install a new thrust plate.
CHECKING TIMING CHAIN SLACK
This procedure applies to all models that use a timing chain.
See Figure 9
- Position a scale (ruler of straightedge) next to the timing chain to detect any movement in the chain.
- Place a torque wrench and socket on the camshaft sprocket attaching bolt. If the cylinder heads are installed on the engine, apply 30 ft. lbs. (41 Nm). If the heads are removed, apply 15 ft. lbs. (20 Nm) of force to the bolt and rotate the bolt in the direction of crankshaft rotation in order to remove all slack from the chain.
- While applying torque to the camshaft sprocket bolt, the crankshaft should not be allowed to rotate. It may be necessary to block the crankshaft to prevent its rotation.
- Position the scale over the edge of a timing chain link and apply an equal amount of torque in the opposite direction. If the movement of the chain exceeds 1 / 8 in. (3mm), replace the chain.