Jeep Engines - Oljeep

4.2L IN-LINE 6 (BLOCK) 285Disassembly1.2.3.4.5.6.7.8.9.10.11.Remove the water pump and fuel pump from thecylinder block.Remove the vibration damper.Remove the crankshaft oil seal.Remove the timing case cover.Remove the oil slinger from the crankshaft.Remove the camshaft retaining bolt and remove thesprockets and chain as an assembly.Remove the camshaft.Remove the oil pan, the gaskets, and the seals.Thoroughly clean the pan and engine block gasketsurfaces.Remove the oil pump.Remove the connecting rods and the pistons. Removethe connecting rod and piston assemblies through thetop of the cylinder bores.Caution: Be sure that the connecting rod bolts DONOT scratch the crankshaft journals or cylinder walls.Short pieces of rubber hose slipped over the connectingrod bolts will provide protection during removal.Remove the crankshaft.Cylinder Bore Measurement1.2.3.4.5.6.Use a bore gauge to measure each cylinder borediameter. If a bore gauge is not available, use an insidemicrometer.Measure the cylinder bore diameter crosswise to thecylinder block near the top of the bore. Repeat themeasurement at the bottom of the bore.Determine the taper by subtracting the smallerdiameter from the larger diameter.Rotate the measuring device 120" and repeat stepsabove. Finally, rotate the device another 120" andrepeat the measurements.Determine out-of-roundness by comparing thedifference between each 120" measurement.If the cylinder bore taper does not exceed 0.025 mm(0.001 ") and the out-of-roundness does not exceed0.025 mm (0.001"), the cylinder bore can be trued byhoning. If the cylinder bore taper or out-of-roundcondition exceeds these maximum limits, the cylindermust be bored and then honed to accept an oversizepiston. A slight amount of taper always exists in thecylinder bore after the engine has been in use for aperiod of time.Cylinder Bore ResurfacingCaution: DO NOT use rigid type hones to removecylinder wall glaze.1. Use an expanding type hone to true the cylinder boreand to remove the glaze for faster piston ring seating.Move the hone down and up (stroke) at sufficientspeed to produce a uniform 60" angle crosshatchpattern on the cylinder walls. DO NOT use more thanten strokes per cylinder (one stroke is one down-andupmovement). Refer to "Block' section of Chapter 4for more information.2. Scrub the cylinder bores clean with a solution of hotwater and detergent.3.Immediately apply light engine oil to the cylinderwalls. Wipe with a clean, lint-free cloth.Assembly1.2.3.4.5.6.7.8.9.Install the crankshaft.Install the connecting rods and the pistons through thetop of the cylinder bores.Caution: Be sure that the connecting rod bolts DONOT scratch the crankshaft journals or cylinder walls.Short pieces of rubber hose slipped over the connectingrod bolts will provide protection during removal.Install the oil pump.Install the oil pan, gaskets and seals.Install the camshaft.Install the camshaft retaining bolt and install thesprockets and chain as an assembly.Install the oil slinger on the crankshaft.Install the timing case cover.Install the crankshaft oil seal.10. Install the vibration damper.11. Install the water pump and fuel pump to the cylinderblock.ENGINE MOUNTSResilient rubber cushions support the engine andtransmission at three points: at each side on the centerlineof the engine and at the rear between the transmissionextension housing and the rear support crossmember.Replacement of a cushion may be accomplished bysupporting the weight of the engine or transmission at thearea of the cushion.