CASE (Left Hand) 4K6944 - Caterpillar

TECHNICAL INFORMATION BULLETIN July 27, 2005
Electric Power Generation
SR4 1MS00744, 4SJ01685, 6EJ01602, 6EJ01606, 6ZW02647-2665, 6ZW02667-2668, 6ZW02671-2672, 6ZW2677-2679, 6ZW02681 6ZW02697-2698, 8SW00690-0694, 9DW00812-0813, 9HW00443-0446, 9LW001131, 9LW01139, 9LW01144, 9RW01613-1634, 9RW01661, 9RW01663-1668, 9RW01670, 9RW01676, 9RW01678
SR4B AER00457-0507, AER00511, AER00515, AER00518, AFE00612-0638, AFH00368-0378, AFH00380-0389, AFK00674-0680, AFK00682-0713, AFK00715-00726, AFK00728-0729, AFK00731, AFN00968-0984, AFN00986-1096, AFN01098, AFR00626-00672, AFR00675-0676, AGE01089-1164, AGE1166-1172, AGE01174-1179, AGE01183-1188, AGE01190, AGE01192
Component Code(s) 1404SUBJECT: 590 to 599 Frame Generator Flex Plate Bolts Susceptible to Breaking.
PROBLEM:
Some of the bolts used to attach the flex plates to the generator rotor shaft hub on 590 to 599 frame generators have lost their head at low hours due to a bolt quality issue. The failed head is contained in the cavity formed by the engine flywheel and the flex plates. The suspect bolts can be identified by the markings on the bolt head, "DB" with three dots underneath per picture MVC-003F. Other bolts are also used, a standard hex-head Grade-8 or a 12-point bolt marked with "F-C" per picture MVC-005F, these bolts are not affected by this problem.
SOLUTION:
Replacement bolts, 9X-2119(available from Morton) are good. These bolts are marked with "F-C" per picture MVC-005F. A standard hex-head Greade-8 bolt, 8T-9400, can also be used as a replacement bolt. A program will be issued to replace the affected suspect bolts.
MVC-003F
MVC-005F
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