CAMSHAFT
NOTE: This procedure requires use of Miller Tool 8502 Tappet Replacement Kit, or Cummins Tool Kit #3822513.
Or
NOTE: To avoid having to obtain special tools noted above, Dowels can be formulated out of ½” Wooden dowel Stock cut to 1” longer than Push Rods. Cut into end ¼” to ½” to allow easier installation into Tappet bores.
REMOVAL
- Disconnect both battery negative cables.
- Recover A/C refrigerant (if A/C equipped) Refer to Group 24, Heating and Air Conditioning for the correct procedure.
- Raise vehicle on hoist.
- Drain engine coolant into container suitable for re-use.
- Lower vehicle.
- Remove radiator upper hose.
- Remove viscous fan/drive assembly.
- Disconnect the coolant recovery bottle hose from the radiator filler neck.
- Remove cooling fan shroud.
- Disconnect lower radiator hose from radiator outlet.
- Automatic Transmission models: Disconnect transmission oil cooler lines from radiator using Special Tool 6931 (unless equipped with finger-release disconnect)
- Remove radiator mounting screws and lift radiator out of engine compartment.
- Remove upper radiator support panel.
- Remove front bumper assembly. Refer to Group 13, Frame and Bumpers for the correct procedure.
- If A/C equipped, disconnect A/C condenser refrigerant lines. Refer to Group 24, Heating and Air Conditioning for the correct procedures.
- Disconnect charge air cooler piping from the cooler inlet and outlet.
- Remove the two charge air cooler mounting bolts.
- Remove charge air cooler (and A/C condenser if equipped) from vehicle.
- Remove accessory drive belt. Refer to Group 7, Cooling System for the correct procedure.
- Remove the fan support/hub assembly Fan Support/Hub Removal/Installation
- Remove crankshaft damper Crankshaft Damper Removal/Installation
- Remove the pump gear access cover by rotating counterclockwise Removing Injection Pump Gear Access Cover
- Using an engine barring tool, rotate the crankshaft to bring the engine to TDC #1.
- Remove the gear cover-to-housing bolts and gently pry the cover away from the housing, taking care not to mar the sealing surfaces.
- Remove the cylinder head cover Cylinder Head Cover Removal/Installation
- Remove the rocker arms Rocker Arm and Pedestal Removal/Installation , cross heads, and push rods Push Rod Removal/Installation Mark each component so they can be installed in their original positions
NOTE: The #5 cylinder exhaust and the #6 cylinder intake and exhaust pushrods are removed by lifting them up and through the provided cowl panel access holes. Remove the rubber plugs to expose these relief holes
- Raise the tappets as follows, using the wooden dowel rods Use Wooden Dowel Rods to Secure Tappets in Place provided with the Miller Tool Kit 8502 or Cummins tappet replacement tool kit #3822513:
- Insert the slotted end of the dowel rod into the tappet. The dowel rods for the rear two cylinders will have to be cut for cowl panel clearance. Press firmly to ensure that it is seated in the tappet.
- Raise the dowel rod to bring the tappet to the top of its travel, and wrap a rubber band around the dowel rods Use Wooden Dowel Rods to Secure Tappets in Place to prevent the tappets from dropping into the crankcase.
- Repeat this procedure for the remaining cylinders.
- Verify that the camshaft timing marks are aligned with the crankshaft and injection pump marks Timing Mark Alignment
- Remove the bolts from the thrust plate Thrust Plate Bolt Location
CAUTION: When removing the camshaft and thrust plate, grab the thrust plate to prevent it from falling into the crankcase.
- Remove the camshaft Camshaft Removal/Installation and thrust plate.
CLEANING
Clean the camshaft with a suitable solvent. Rinse in hot water and blow dry with compressed air.
INSPECTION
Camshaft
- Inspect the valve lobes and bearing journals for cracks, pitting, scoring, or generally excessive wear. Replace any camshaft that exceeds the allowable limits.
- Measure the bearing journals and lobes
CAUTION: If Camshaft lobes are worn, requiring camshaft replacement, it is necessary to replace the tappets also. Refer to Tappet Removal and Installation in this group
Camshaft Journal DiameterJournal #1 54.028 mm (2.1270 in.) MIN.
Journal #2-7 53.987 mm (2.1245 in.) MIN.
Camshaft Lobe Height
Intake Lobe 47.173 mm (1.857 in.) MIN.
Exhaust Lobe 45.636 mm (1.796 in.) MIN.
Camshaft Bushing/Bores
Camshaft bores No. 2 - 7 do not use a bushing.
- Inspect the camshaft bushing and bores for signs of excessive wear.
- Measure the camshaft bushing and bores with a telescoping bore gauge and micrometer. If out of specification, refer to Camshaft Bushing Removal and Installation for replacement procedures.
- Inspect the camshaft bushing oil hole for alignment with cylinder block
Camshaft Gear
Inspect the camshaft gear for cracks (gear and hub) , and chipped/broken/fretted teeth If replacement is necessary, refer to Camshaft Gear Removal and Installation in this section
Thrust Plate
Inspect the camshaft thrust plate for excessive wear in the camshaft contact area. Measure thrust plate thickness using the following chart. Replace any thrust plate that falls outside of these specifications:
CAMSHAFT THRUST PLATE THICKNESS9.34 mm (0.368 in.) MIN.
9.58 mm (0.377 in.) MAX.
BUSHING REPLACEMENT
- Measure the diameter of each bore. (The limit for the bushing in the No.1 bore is the same as for the other bores without bushings) The limit of the inside diameter is 54.133 mm (2.1312 inch) If the camshaft bore for the first cam bushing is worn beyond the limit, install a new service bushing. Inspect the rest of the camshaft bores for damage or excessive wear.
- If the bores without a bushing are worn beyond the limit, the engine must be removed for machining and installation of service bushings. If badly worn, replace the cylinder block.
- Remove the bushing from the No.1 bore, using a universal cam bushing tool.
- Mark the cylinder block so you can align the oil hole in the cylinder block with the oil hole in the bushing.Apply a coating of Loctite® 640 Adhesive to the backside of the new bushing. Avoid getting adhesive in the oil hole.
- Use a universal cam bushing installation tool and install the bushing so that it is even with the front face of the cylinder block. The oil hole must be aligned. A 3.2 mm (0.128 inch) diameter rod must be able to pass through the hole
- Measure the installed bushing. The limit of the inside diameter is 54.133 mm (2.1312 inch)
INSTALLATION
- Lubricate the camshaft bushing and bores with fresh engine oil or suitable equivalent.
- Liberally coat the camshaft lobes, journals, and thrust washer with fresh engine oil or suitable equivalent
CAUTION: When installing the camshaft , DO NOT push it in farther than it will go with the thrust washer in place. Pushing it too far can dislodge the plug in the rear of the camshaft bore and cause an oil leak.
- Install the camshaft Camshaft Removal/Installation and thrust plate. Align the timing marks as shown in Timing Mark Alignment
- Install the thrust plate bolts and tighten to 24 N·m (18 ft. lbs.) torque.
- Measure camshaft back lash and end clearance
BACKLASH - 0.080 - 0.330 mm(0.003 - 0.013 inch)
CLEARANCE - 0.152 - 0.254 mm(0.006 - 0.010 inch)
- Remove the wooden dowel rods and rubber bands from the tappets.
- Lubricate the push rods with engine oil and install in their original location Push Rod Removal/InstallationVerify that they are seated in the tappets.
- Lubricate the valve tips with engine oil and install the crossheads in their original locations.
- Lubricate the crossheads and push rod sockets with engine oil and install the rocker arms and pedestals in their original locations Rocker Arm and Pedestal Removal/Installation Tighten bolts to 36 N·m (27 ft. lbs.) torque.
- Verify valve lash adjustment. Refer to Valve Lash Verification and Adjustment in Service Procedures.
- Install the cylinder head cover and reusable gasket Cylinder Head Cover Removal/Installation Torque bolts to 24 N·m (18 ft. lbs.)
- Apply a bead of Mopar® Silicone Rubber Adhesive Sealant or equivalent to the gear housing cover. Install and tighten bolts to 24 N·m (18 ft. lbs.) torque.
- Install the crankshaft damper Crankshaft Damper Removal/Installation and tighten bolts to 125 N·m (92 ft. lbs.) torque.
- Install the fan support/hub assembly Fan Support/Hub Removal/Installation and tighten bolts to 24 N·m (18 ft. lbs.) torque.
- Install the fuel pump gear access cover. Tighten clockwise by hand.
- Install the charge air cooler (with a/c condenser and auxiliary transmission oil cooler, if equipped) and tighten the mounting bolts to 2 N·m (17 in. lbs.) torque.
- Connect charge air cooler inlet and outlet pipes. Tighten clamps to 10 N·m (100 in. lbs.) torque.
- Install the radiator upper support panel.
- Close radiator petcock and lower the radiator into the engine compartment. Tighten the mounting bolts to 11 N·m (95 in. lbs.) torque.
- Raise vehicle on hoist.
- Connect radiator lower hose and install clamp.
- Connect transmission auxiliary oil cooler lines (if equipped)
- Lower vehicle.
- Install the fan shroud and tighten the mounting screws to 6 N·m (50 in. lbs.) torque.
- Install the viscous fan/drive assembly and tighten to 57 N·m (42 ft. lbs.) torque.
- Install the coolant recovery and windshield washer fluid reservoirs to the fan shroud.
- Connect the coolant recovery hose to the radiator filler neck.
- Install the accessory drive belt. Refer to Group 7, Cooling for the correct procedure.
- Install the front bumper assembly. Refer to Group 13, Frame and Bumper for the correct procedure.
- Add engine coolant.
- Connect the battery negative cables.
- Start engine and check for engine oil and coolant leaks.
- Charge A/C system with refrigerant (if A/C equipped) Refer to Group 24, Heating and Air Conditioning for the correct procedure.