Jeep Engines - Oljeep

TT74.2L IN-LINE 6 (PISTON AND CONNECTING ROD ASSEMBLY) 2938. If the correct clearance is indicated, replacement of thebearing inserts is not necessary. Remove thePlastigauge from crankshaft journal and bearing insert.Proceed with installation.9. If bearing-to-journal clearance exceeds thespecification, install a pair of 0.0254 mm (0.001")undersize bearing inserts. Measure the clearance asdescribed in the previous steps.10. The clearance measured with a pair of 0.0254 mm(0.001 'I) undersize bearing inserts installed willdetermine if two 0.0254 mm (0.001 ") undersize inserts oranother combination is needed to provide the correctclearance.Example: If the initial clearance was 0.0762 mm(0.003"), 0.025 mm (0.00 1 ") undersize inserts wouldreduce the clearance by 0.025 mm (0,001"). Theclearance would be 0.002" and within specification. A0.05 1 mm (0.002") undersize insert would reduce theinitial clearance an additional 0.01 3 mm (0.0005").The clearance would then be 0.038 mm (0.001 5").11. Repeat the Plastigauge measurement to verify yourbearing selection prior to final assembly.12. Once you have selected the proper insert, install theinsert and cap. Tighten the connecting rod bolts to 45Nem (33 ft-lbs) torque.Side Clearance MeasurementSlide snug-fitting feeler gauge between the connecting rodand crankshaft journal flange. The correct clearance is0.254 to ,482 mm (0.010 to 0.019"). Replace the connectingrod if the side clearance is not within specification.I. Clean the cylinder bores thoroughly. Apply a light filmof clean engine oil to the bores with a clean lint-freecloth.2. Install the piston rings on the pistons, if removed.3. Lubricate the piston and rings with clean engine oil.Caution: Ensure that connecting rod bolts DO NOTscratch the crankshaft journals or cylinder walls. Shortpieces of rubber hose slipped over the connecting rod boltswill provide protection during installation.4. Use a piston ring compressor to install the connecting rodand piston assemblies through the top of the cylinderbores.5. Ensure the arrow on the piston top points to the frontof the engine.6. Raise the vehicle.Caution: Verify that the oil squirt holes in the connectingrods face the camshaft and that the arrows on the pistonsface the front of the engine.7. Install the connecting rod bearing caps and inserts inthe same positions as removed.8. Install the oil pan and gaskets. Refer to Oil PunInstullution, 'Oiling System' section, for the properprocedure.9. Lower the vehicle.10. Install the cylinder head, pushrods, rocker arms,bridges, pivots and cylinder head cover. Refer to'Cylinder Head' section for the proper procedures.1 1. Fill the crankcase with engine oil.InstallationEach bearing insert is selectively fitted to its respectivejournal to obtain the specified operating clearance betweenthe bearing and the journal. In production, the select fit isobtained by using various-sized, color-coded bearing inserts.The color code appears on the edge of the bearing insert. Thesize is not stamped on inserts used for production of engines.The rod journal is identitied during the engine production bya color-coded paint mark on the adjacent check orcounterweight toward the flanged (rear end of the crankshaft).When required, upper and lower bearing inserts of differentsizes may be used as a pair. A standard size insert issometimes used in combination with a 0.025 mm (0.001")undersize insert to reduce clearance 0.0 13 mm (0.0005").Caution: DO NOT intermix bearing caps. Each connectingrod and its bearing cap are stamped with the associatedcylinder number on a machined surface adjacent to the oilsquirt hole that faces the camshaft side of the cylinder block.