NUT-SPECIAL 2467854 - Caterpillar

D379 (68B, 69B, 34Z) D398 (66B, 67B, 35Z) D399 (35B, 91B, 36Z) G379 (72B) G398 (73B) G399 (49C)The new crankshaft seal conversion groups and crankshaft seal groups given above are available from the Parts Department. The 4W2568, 4W2569, 4W2570 and 4W2571 Crankshaft Seal Conversion Groups are used to convert earlier engines that have either a piston-type seal with a baffle and thrower, or later engines that have a lip-type seal and wear sleeve. The 4W2606 or 4W2607 Crankshaft Seal Group is used as a replacement seal group for those earlier engines that have been equipped with a conversion group, or those later engines that have the new type seal as original equipment. See the chart that follows for adaptability of the seal groups.The new seal is quite different from the former seal because of the hydrodynamic groove in the sealing lip of the new seal. These grooves in the seal lip move lubrication oil back into the engine crankcase as the crankshaft turns. Because of this type design, the front seal group for an engine is different from the rear seal group. The installed position of the seal lip grooves is important, because the grooves are very sensitive to the direction of crankshaft rotation. If a specific seal group is installed on the wrong end of the engine, lubrication oil can actually be taken out of the engine, because the grooves in the seal lip are in the wrong direction in relation to crankshaft rotation. See the chart that follows for seal group use according to crankshaft rotation. IMPORTANT: Because of the special design of these new seal groups, special handling and installation procedures are necessary, to help prevent additional failures.(1) Seal Group Installation Tools
1 - 6V7831 Installer. 2 - 6V7829 Locator. 3 - 6V7834 Bolt (two), 1.00"-14 x 50.8 (2.0") long; 6V9442 Bolt (two), 7/8"-14 x 60.3 (2.4") long. 4 - 9S8858 Nut. 5 - 6V7833 Ring. 6 - 6V7799 Ring. 7 - 4B5271 Washer (six). 8 - 3B1915 Bolt (six), 3/8"-16 x 34.92 (1.375") long. Also needed, but not shown, are L1143 Bolts (six) 3/8" - 16 X 63.5 (2.50") long. Check thickness (A) of 6V7829 Locator (2). Thickness (A) must be 33.0 mm (1.300"). Any locator that is thicker than the 33.0 mm (1.300") dimension must be machined to the new thickness.(2) Separation Of The Seal From The Sleeve Is Not Permissible
The material in the large lip of the seal can be damaged easily. Fingers, fingernails, wires or the edge of the sleeve can put a scratch on the surface of the seal lip. It is possible that a scratch or a rub (which can not be seen) from a finger, can damage the seal enough that it can not be used. In these seal groups, the sleeve is installed in the seal, by the seal group supplier, for two very good reasons, as follows:A. To give better protection to the special material on the seal lip.B. To make for easier installation. The seal and