TM 10-3930-660-34 3-8. CRANKSHAFT - REPLACE/REPAIR (Cont’d) NOTE Wear sleeves are used only if seal surfaces were damaged and the surface was machined to allow for sleeve installation. 2.   INSTALL WEAR SLEEVES (19 AND 20). a. Install new front wear sleeve (19) over end of crankshaft (14). b. Install new rear wear sleeve (20) over end of crankshaft (14). INSTALLATION 1.   CLEAN MAIN BEARING SURFACES IN CYLINDER BLOCK, PARA.  3-9. NOTE If the crankshaft journals have been ground, appropriate oversize bearings will need to be installed. 2.   CHECK MAIN BEARING AND THRUST BEARING CLEARANCE. NOTE Install new main bearings dry at this time.  Be sure cylinder block bearing bores, backsides of bearings, and inner surface of bearing caps are clean and dry. a. Align tab of new upper bearing half (17) with groove in crankshaft bearing bore (cylinder block), and press bearing half into place. Perform this procedure for main bearing positions 1 through 5 and 7. b. Install thrust bearing (18) in crankshaft bearing bore no.  6 with tab in bearing bore groove. 3-58