Jeep Cherokee (XJ): Disassembly and assembly. Cleaning and inspection. Specifications

Jeep Cherokee (XJ) 1984 - 2001 Service Manual > Engine > 2.5L engine > Disassembly and assembly. Cleaning and inspection. Specifications

Disassembly and assembly

CYLINDER BLOCK

DISASSEMBLY

(1) Drain the engine oil. Remove and discard the oil filter.

(2) Remove the water pump from the cylinder block.

(3) Remove the distributor from the cylinder block.

(4) Remove the vibration damper.

(5) Remove the timing case cover and lay the cover upside down.

(6) Position a drift punch into the slot in the back of the cover and tap the old seal out.

(7) Remove the timing chain bumper.

(8) Remove the oil slinger from crankshaft.

(9) Remove the camshaft retaining bolt and remove the sprockets and chain as an assembly.

(10) Remove the camshaft.

(11) Remove the oil pan and gasket.

(12) Remove the timing chain tensioner.

(13) Remove the front and rear oil galley plugs.

(14) Remove the connecting rods and the pistons.

Remove the connecting rod and piston assemblies through the top of the cylinder bores.

(15) Remove the crankshaft.

ASSEMBLY

(1) Install the crankshaft.

(2) Install the connecting rods and the pistons through the top of the cylinder bores.

(3) Install the front and rear oil galley plugs.

(4) Install the timing chain tensioner.

(5) Install the camshaft.

(6) Install the sprockets and chain as an assembly.

(7) Install the oil slinger to the crankshaft.

(8) Install the timing chain bumper.

(9) Install the timing case cover seal.

(10) Install the timing case cover.

(11) Install the oil pan gasket and oil pan.

(12) Install the vibration damper.

(13) Install the water pump. Tighten the mounting bolts to 31 N·m (270 in. lbs.) torque.

(14) Remove the distributor from the cylinder block.

(15) Lubricate the oil filter seal with clean engine oil. Tighten oil filter to 18 N·m (13 ft. lbs.) torque.

(16) Install the engine into the vehicle.

(17) Fill the engine with clean lubrication oil.

(18) Fill the cooling system.

Cleaning and inspection

Rocker arms and push rods

CLEANING

Clean all the components with cleaning solvent.

Use compressed air to blow out the oil passages in the rocker arms and push rods.

INSPECTION

Inspect the pivot surface area of each rocker arm.

Replace any that are scuffed, pitted, cracked or excessively worn

Inspect the valve stem tip contact surface of each rocker arm and replace any rocker arm that is deeply pitted.

Inspect each push rod end for excessive wear and replace as required. If any push rod is excessively worn because of lack of oil, replace it and inspect the corresponding hydraulic tappet for excessive wear.

Inspect the push rods for straightness by rolling them on a flat surface or by shining a light between the push rod and the flat surface.

A wear pattern along the length of the push rod is not normal. Inspect the engine cylinder head for obstruction if this condition exists.

Engine cylinder head

CLEANING

Thoroughly clean the engine cylinder head and cylinder block mating surfaces. Clean the intake and exhaust manifold and engine cylinder head mating surfaces. Remove all gasket material and carbon.

Check to ensure that no coolant or foreign material has fallen into the tappet bore area.

Remove the carbon deposits from the combustion chambers and top of the pistons.

INSPECTION

Use a straightedge and feeler gauge to check the flatness of the engine cylinder head and block mating surfaces.

Cylinder block

CLEANING

Thoroughly clean the oil pan and engine block gasket surfaces.

Use compressed air to clean out:

  •  The galley at the oil filter adaptor hole, the filter bypass hole (Fig. 89).
  •  The front and rear oil galley holes (Fig. 90) (Fig. 91).
  •  The feed holes for the crankshaft main bearings.

Once the block has been completely cleaned, apply Mopart Thread Sealant with Teflon to the threads of the front and rear oil galley plugs. Tighten the plugs to 41 N·m (30 ft. lbs.) torque.

INSPECTION

Inspect the cylinder bores for signs of scorring, pitting or cracks. If the cylinder bores are scorred or pitted the cylinder bores will require boreing or honing to clean them up. Refer to Honing Cylinder Bores in this Section. If the cylinder bore(s) are cracked the cylinder block must be replaced.

Inspect the cylinder block to cylinder head mating surface for flatness and/or pitting.

Fig. 89 Oil Filter Adaptor Hole
Fig. 89 Oil Filter Adaptor Hole

1 - FILTER BYPASS HOLE
2 - OIL FILTER ADAPTOR HOLE

Fig. 90 Front Oil Galley Hole
Fig. 90 Front Oil Galley Hole

1 - FRONT OIL GALLEY HOLE

Fig. 91 Rear Oil Galley Hole

Fig. 91 Rear Oil Galley Hole

1 - REAR OIL GALLEY HOLE

Specifications

Engine specifications

ENGINE DESCRIPTION

ENGINE DESCRIPTION

ENGINE DESCRIPTION

ENGINE DESCRIPTION

ENGINE DESCRIPTION

ENGINE DESCRIPTION

ENGINE DESCRIPTION

ENGINE DESCRIPTION

ENGINE DESCRIPTION

Specifications-torque

TORQUE CHART 2.5L ENGINE

TORQUE CHART 2.5L ENGINE

TORQUE CHART 2.5L ENGINE

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