Jeep Engines - Oljeep

2.5L POWER TECH IN-LINE 4 (PISTONS AND RINGS) 47The rod journal is identified during engine production by acolor-coded paint mark on the adjacent cheek orcounterweight toward the flanged (rear) end of thecrankshaft. The color codes used to indicate journal sizesare listed in the Connecting Rod Bearing Fitting Chart(Figure 2-32).InstallationCONNECTING ROD J9009-40Figure 2 - 35Figure 2 - 3619509-86Each bearing insert is selectively fit to its respective journalto obtain the specified operating clearance between thebearing and the journal. In production, the select fit isobtained by using various sized, color-coded bearing insertsas listed in the Connecting Rod Bearing Fitting Chart(Figure 2-32). The color code appears on the edge of thebearing insert. The size is not stamped on inserts used forproduction of engines.When required, upper and lower bearing inserts of differentsizes may be used as a pair (see Connecting Rod BearingFitting Chart, Figure 2-32). A standard size insert issometimes used in combination with a 0.025 mm (0.001")undersize insert to reduce clearance 0.013 mm (0.00OS").Caution: DO NOT intermix bearing caps. Eachconnecting rod and its bearing cap are stamped with theassociated cylinder number on a machine surface adjacentto the oil squirt hole that faces the camshaft side of thecylinder block (Figure 2-35).1.2.3.4.5.6.7.8.9.Clean the cylinder bores thoroughly. Apply a light film ofclean engine oil to the bores with a clean lint-free cloth.Install the piston rings on the pistons if removed.Refer to Piston Ring Fitting, this section, for theproper procedure.Lubricate the piston and rings with clean engine oil.Use a piston ring compressor to install the connectingrod and piston assemblies through the top of thecylinder bores (Figure 2-36).Caution: Ensure that connecting rod bolts DO NOTscratch the crankshaft journals or cylinder walls. Shortpieces of rubber hose slipped over the connecting rodbolts will provide protection during installation.Ensure the arrow on the piston top points to the frontof the engine (Figure 2-37).Note: For racing applications, refer to ReversingPistons with Oflset Pins, 'Pistons and Rings' section ofChapter 4.Raise the vehicle.Install the connecting rod bearing caps and inserts inthe same positions as removed.Caution: Verify that the oil squirt holes in the rodsface the camshaft and that the arrows on the pistonsface the front of the engine.Install the oil pan and gaskets as outlined in theinstallation procedure.Lower the vehicle.10. Install the cylinder head, pushrods, rocker arms,bridges, pivots and cylinder head cover as outlined inthe installation procedures in this chapter.11. Fill the crankcase with engine oil.