CORE-VALVE 6F3930 - Caterpillar

3508, 3512 Industrial, Marine, Generator Set, Vehicular EnginesDescription of Change: An improvement has been made to the 1N4679 Control Rod Assembly for 3508 and 3512 Industrial, Marine, Generator Set and Vehicular Engines. The 7N5372 Rod Assembly, which is no longer available separately, is part of the 1N4679 Control Rod Assembly used in the fuel injection control group. See the illustration. The adjustment range of the rod assembly has been increased from approximately 5 mm (.2") to 12 mm (.5"). This permits the serviceman to adjust the control group so that the unit injector racks are synchronized (adjusted to operate at the same time and at the same rate). Formerly, the rod assembly at times, was adjusted to the limit, but the racks were not synchronized.
Adaptable To: The improved 1N4679 Control Rod Assembly is in effect with Serial Numbers 23Z441, 24Z552, 49Y406, 50Y488, 51Y467, 65Z589, 67Z490, 95Y617 and 96Y590. It is adaptable to all earlier engines. If the dealers' parts stocks have 7N5372 Rod Assemblies, the rod assemblies can be used only if the shorter range of adjustment permits the racks to be synchronized. If the rod assemblies do not permit the racks to be synchronized, remove the 7N5372 Rod Assembly, the 7N5367 Dowel and the 1N4673 Lever from the engine and install a 1N4679 Control Rod Assembly. The 7N5372 Rod Assembly, the 7N5367 Dowel and the 1N4673 Lever which make up the 1N4679 Control Rod Assembly are not available as replacement parts.
Location of the 1N4679 Control Rod Assembly.