HOUSING-FLYWHEEL 2123686 - Caterpillar

(1) Diameter of the surfaces (journals) for the camshaft bearings (new) ... 2.5000 .0005 in.(63.500 0.013 mm) Bore in the five bearings for the camshaft (new) ... 2.5035 .0015 in.(63.589 0.038 mm)Maximum permissible clearance between bearing and bearing surface (journal) (worn) ... .007 in.(0.18 mm)(2) Tight fit between the gear and camshaft ... .0012 to .0028 in.(0.030 to 0.071 mm) Maximum permissible temperature of the gear for installation on the camshaft (do not use a torch) ... 600° F(315° C)(3) End play for the camshaft ... .007 .003 in.(0.18 0.08 mm) Maximum permissible end play (worn) ... .020 in.(0.51 mm)(4) Width of thrust groove in camshaft (new) ... .360 .002 in.(9.14 0.05 mm) Diameter of thrust pin (new) ... .353 .001 in.(8.97 0.03 mm)Torque for thrust pin ... 35 5 lb. ft.(45 7 N m) For installation of camshaft, the timing mark on the camshaft gear tooth must be in alignment with the timing mark on the tooth space of the crankshaft gear. (5) Height of camshaft lobes. To find lobe lift, use the following procedure:A. Measure camshaft lobe height (5).B. Measure base circle (7).C. Subtract base circle (STEP B) from lobe height (STEP A). The difference is actual lobe lift (6).D. Specified camshaft lobe lift (6) is: a. Exhaust lobe ... .3071 in.(7.800 mm)b. Intake lobe ... .3077 in.(7.816 mm)Maximum permissible difference between actual lobe lift (STEP C) and specified lobe lift (STEP D) is .010 in. (0.25 mm).