PULLEY-AUXILIARY DRIVE 9N5012 - Caterpillar

3606 (8RB),
3608 (6MC),
3612 (9RC),
3616 (1PD),
G3606 (3XF),
G3608 (4WF),
G3612 (1YG),
G3616 (4CG) EnginesDescription of Change: A new coupling guard support group is used to attach to the coupling guard groups on these engines. This coupling guard support group includes leg assemblies which provide support to the rear portion of the coupling guard. The addition of the supports will help prevent cracks in the backing plate assemblies that are due to excessive vibratory stress. The length of the supports are adjustable to fit various applications.Adaptable To: The components of the new 174-9798 Coupling Guard Support Group are identified in the chart and the illustration. The 174-9798 Coupling Guard Support Group is effective with 3606 (8RB741), 3608 (6MC599), 3612 (9RC305), 3616 (1PD353), G3606 (3XF211), G3608 (4WF127), G3612 (1YG177), and G3616 (4CG140). The coupling guard support group is adaptable to all earlier engine serial numbers.
(LEFT SIDE VIEW OF ENGINE) Identification of components in the 174-9798 Coupling Guard Support Group Installation Procedure For The 174-9798 Coupling Guard Support Group
Make sure that the coupling guard is properly located on the engine. There must be sufficient radial clearance between the guard and the coupling all the way around. In order to reduce installation time, perform Steps 1 through 6 on one side of the engine first (left or right), and then repeat for the other side.1. Remove the nut, bolt, and washers at location (A).2. Insert one lower leg assembly (4) into an upper leg assembly (3).3. Place the leg assemblies in position so that the top of the upper leg assembly lines up with the hole in the coupling guard at (A) and the bottom of the leg assembly is resting on the engine base. Attach the leg assembly in position at (A) using a bolt (1) and washer (2). Leave the bolt only finger tight. If the leg assembly does not rest flat on the engine base, weld a plate to the engine base to attach the lower leg assembly.4. Using the holes in the lower leg assembly (4) as a guide, drill and tap two holes for 3/8-16 bolts in the engine base (or in the plate that was welded on).5. Bolt the lower leg assembly (4) in place on the engine base.6. Tighten bolt (1) at (A).7. Repeat Steps 1 through 6 for the other side of the engine.8. Make sure that the leg assemblies are positioned (extended) properly to support the weight of the coupling guard. Weld the upper leg assemblies to the lower leg assemblies at area (B).