Here's a How-To:
Timing Belt Cover and Seal
REMOVAL & INSTALLATION
Release the fuel system pressure using the recommended procedure.
Rotate the engine to Top Dead Center (TDC) and disconnect negative battery cable.
Drain the coolant and remove the radiator and cooling fan assemblies.
Remove the accessory drive belts.
Remove the upper radiator hose.
Remove the crankshaft damper with a quality puller tool gripping the inside of the pulley.
Remove the stamped steel cover. Do not remove the sealer on the cover. It may be reusable.
Remove the cast cover. If necessary, remove the lower belt cover located behind the crankshaft damper.
Before installing, inspect the seal on the stamped steel cover. Is some sealer is missing, use MOPAR Silicone Rubber Adhesive Sealant or equivalent to replace the missing sealer.
Install the lower belt cover behind the crankshaft damper, if necessary.
Install the stamped steel cover and the cast cover. Tighten the 6mm bolts to 105 inch. lbs. (12 Nm), the 8mm bolts to 250 inch lbs. (28 Nm) and the 10mm bolts to 40 ft. lbs. (54 Nm).
Install the crankshaft damper using special tool L-4524, a 5.9 inch long bolt, thrust bearing and washer or equivalent damper installation tools. Tighten the center bolt to 85 ft. lbs. (115 Nm).
Install the upper radiator hose.
Install the accessory drive belts and adjust them to the proper tension.
Install the radiator and cooling fan assemblies.
Refill and bleed the cooling system.
Reconnect the negative battery cable. With the radiator cap off so coolant can be added, run the engine. Watch for leaks or unusual engine noises. Add coolant as the engine warms.
See Figures 1, 2, 3, 4, 5, 6, 7 and 8
Fig. 1: Align the crankshaft sprockets between the marks on the rear belt covers-3.5L engine
Fig. 2: Exploded view of the timing belt routing-3.5L engine
Fig. 3: Compress the tensioner plunger in a vise
Fig. 4: Remove the crankshaft sprocket with tool L-4407-A or the equivalent
Fig. 5: Tap out the dowel pin in the crankshaft
Fig. 6: Remove the crankshaft seal with tool 6341A or equivalent
Fig. 7: Install the seal by tapping it into place with the special tool 6342
Fig. 8: Install the crankshaft sprocket as shown
Remove the timing cover as outlined.
If the timing belt is to be reused, mark the timing belt running direction for installation. Align the camshaft sprockets with the marks on the rear covers.
Remove the timing belt and tensioner. Inspect the timing belt for excessive wear, damage and/or deterioration and replace with new belt, if necessary.
Remove the camshaft sprockets, use the following procedure.
Hold the camshaft sprocket with a 36 mm box wrench, loosen and remove the sprocket retaining bolt and washer.
To remove the camshaft sprocket retainer bolt while the engine is in the vehicle, it may be necessary to raise that side of the engine due to the length of the retainer bolt. The right bolt is 8 3/8-inch (213.00 mm) long, while the left bolt is 10.0 inch (254.00 mm) long. These bolts are not interchangeable and their original location during removal should be noted.
Tap the dowel pin out of the crankshaft.
Remove the seal using a special seal puller.
The shaft seal lip surface must be free of varnish, nicks or dirt. Polish it with a 400 grit paper if necessary.
Install the crankshaft seal using a seal installer such as tool, 6342 or equivalent.
Install the dowel pin into the crankshaft to 0.047 inch (1.0mm) protrusion.
Install the camshaft sprockets, using the following procedure.
This procedure can only be used when the camshaft sprockets have been loosened or removed from the camshafts. Each sprocket has a D-shaped hole that allows it to be rotated several degrees in each direction on its shaft. This design must be timed with the engine to ensure proper performance.
Pre-load the belt tensioner as follows:
Place the tensioner in a vise the same way it is mounted on the engine.
Slowly compress the plunger into the tensioner body.
When the plunger is compressed into the tensioner body install a pin through the body and plunger to retain plunger in place until tensioner is installed.
Install both camshaft sprockets to the appropriate shafts. The left camshaft sprocket has the DIS pickup as part of the sprocket.
Apply Loctite® 271 or equivalent, to the threads of the camshaft sprocket retainer bolts and install to the appropriate shafts. The right bolt is 8 3/8-inch (213.00mm) long, while the left bolt is 10.0 inch (254.00 mm) long. These bolts are not interchangeable. Do not tighten the bolts at this time. The camshaft marks should be between the marks on the cover.
Align the camshaft sprockets between the marks on the covers.
Align the crankshaft sprocket with the TDC mark on the oil pump cover.
Install the timing belt starting at the crankshaft sprocket and going in a counterclockwise direction. After the belt is installed on the right sprocket, keep tension on the belt until it is past the tensioner pulley.
Holding the tensioner pulley against the belt, install the timing belt tensioner into the housing and tighten to 21 ft. lbs. (28 Nm).
When the tensioner is in place pull the retainer pin to allow tensioner to extend to the pulley bracket.
Remove the spark plug in the No. 1 cylinder and install a dial indicator to check Top Dead Center (TDC) of the piston. Rotate the crankshaft until the piston is exactly at TDC. Hold the camshaft sprocket hex with a 36 mm wrench and tighten the right camshaft sprocket bolt to 75 ft. lbs. (102 Nm) plus an additional 90 degree turn. Tighten the left camshaft sprocket bolt to 85 ft. lbs. (115 Nm) plus an additional 90 degree turn.
Remove the dial indicator. Install the spark plug and tighten to 20 ft. lbs. (28 Nm).
Remove the camshaft alignment tools from the back of the cylinder heads and install the cam covers and new O-rings. Tighten the fasteners to 20 ft. lbs. (27 Nm). Repeat this procedure on the other camshaft.
Rotate the crankshaft sprocket two revolutions and check for proper alignment of the timing marks on the camshaft and the crankshaft. If the timing marks do not line up, repeat the procedure.
Install the timing cover as outlined in the Timing Cover procedure.
REMOVAL & INSTALLATION
The water pump has a die cast aluminum body and a stamped steel impeller. It bolts directly to the chain case cover using an O-ring for sealing. It is driven by the back side of the serpentine belt.
It is normal for a small amount of coolant to drip from the weep hole located on the water pump body (small black spot). If this condition exists, do NOT replace the water pump. Only replace the water pump if a heavy deposit or steady flow of brown/green coolant is visible on the water pump body from the weep hole, which would indicate shaft seal failure. Before replacing the water pump, be sure to perform a thorough analysis. Before replacing the water pump, be sure to perform a thorough inspection. A defective pump will not be able to circulate heated coolant through the long heater hose.
See Figure 5
Disconnect the negative battery cable.
Place a drain pan under the radiator. Open the radiator drain located at the lower right side of the radiator. Do NOT use pliers to open the plastic drain.
Remove the coolant pressure bottle cap and open the thermostat bleed valve.
Remove the timing belt using the recommended procedure. It is good practice to turn the crankshaft until the engine is at TDC No. 1 cylinder, compression stroke (firing position). This aligns all the timing marks and serves as a reference point for all the work that follows.
Remove the water pump mounting bolts and pump. Discard the O-ring seal.
Clean the gasket sealing surfaces. Do not scratch the aluminum surfaces.
Install a new O-ring and wet with clean coolant. Be sure to keep the new O-ring free of any oil or grease.
Install the water pump and O-ring to the engine block.
Install the retaining bolts and tighten to 105 inch lbs. (12 Nm).
Fig. 5: Tighten the water pump mounting bolts to 105 inch lbs. (12 Nm)
Rotate the pump and check for freedom of movement.
Install the timing belt using the recommended procedure. Verify that all valve timing marks align. This is most important. An engine out-of-time will be seriously damaged when first started.
Be sure that the radiator drain is closed. Open the thermostat bleed valve. Install a 1/4-inch clear hose about 48 inches long to the end of the bleed valve and the other end into a clean container. The intent is to keep coolant off of the drive belt(s).
Slowly refill the coolant pressure bottle until a steady stream of coolant flows out of the thermostat bleed valve. Gently squeeze the upper radiator hose until all of the air is removed from the system.
Close the bleed valve and continue to fill up the coolant pressure bottle to the proper level. Install the cap back on the bottle and remove the hose from the bleed valve.
Reconnect the negative battery cable. Start the engine and allow to run until normal operating temperature is reached.
Check the cooling system for leaks and correct coolant level. Be sure that the thermostat bleed valve is closed once the cooling system has been bled of any trapped air.