Crankshaft and Main Bearings/Crankshaft and Main Bearings NOTE: Original rear bearing uses a separate thrust washer. Replacement rear bearing is a one piece assembly with the thrust washer part of the bearing. 19. If equipped, remove thrust washer and shim. M36341 -UN-29JAN90 M98,2035K,13 -19-10OCT85 CTM2 (19APR90) 35-6 16, 18, 20 & 24HP Onan Engines AllTractorManuals.com 130495 INSPECT CRANKSHAFT AND MAIN BEARINGS 1. Measure crankshaft main bearing journal outside diameter. -UN-29JAN90 NOTE: If engine has had previous major overhaul, crankshaft journals may have been ground and undersize bearings installed. 2. Measure several places around each journal and each M36342 side of both journals.
NOTE: For connecting rod journal specifications, see Piston and Connecting Rods in Group 30 in this section. MAIN BEARING JOURNAL SPECIFICATIONS Item New Parts Wear Tolerance Journal O.D. 50.78—50.80 mm 50.72 mm (1.9992—2.0000 in.) (1.997 in.) If journal diameter is less than 50.72 mm (1.997 in.), replace crankshaft or have journals ground by a qualified machine shop. The following undersize main bearings are available: 0.05 mm (0.002 in.) 0.25 mm (0.010 in.) 0.50 mm (0.020 in.) 0.76 mm (0.030 in.) M98,2035K,14 -19-12NOV85 35 6