PUMP GP-GEAR 2284501 - Caterpillar

3508 (96Y, 69Z);
3512 (50Y, 66Z);
3516 (29Z, 72Z)This instruction gives the procedure to put the above engines in alignment with and connect them to 7271 Caterpillar Marine Transmissions. Two types of flexible couplings are used to connect the engine to the transmission: 8N8872 Coupling Group uses ten rubber blocks as the flexible coupling, while 2W6514 and 2W6943 Coupling Groups use rubber discs for the flexible coupling. The alignment procedure is the same for both type couplings. Use Special Instruction Form SEHS7456-01, ALIGNMENT OF CATERPILLAR MARINE TRANSMISSIONS AND MARINE ENGINES and Form SEHS7654, ALIGNMENT - GENERAL INSTRUCTIONS, along with this instruction for the correct alignment and installation procedures.Put the marine transmission in alignment with the ship's propeller shaft as shown in Special Instruction Forms SEHS7456-01 and SEHS7654. Fasten the marine transmission to the ship's rails.Since not all dial indicators indicate plus (+) in the same direction, it is necessary that a standard be established for the purpose of clarity in this instruction. In this instruction a plus (+) reading means that the tip of the indicator moved into the dial indicator; a minus (-) reading means that the tip of the indicator moved out of the dial indicator. Before taking any indicator readings, check the dial indicators being used to determine which is the plus (+) direction. If the plus (+) direction is different than the standard used in this instruction, keep this in mind when taking dial indicator readings.8N8872 Coupling Group
(1) Remove cover (1) and rubber blocks (2) from coupling assembly (3). Install coupling assembly (3) on the flywheel. Use an 8S2328 Dial Indicator Group to measure the TIR (total indicator runout) at four places 90° apart around machined surfaces (Z) and (Y) on coupling (3). Use a pry bar to move the crankshaft to the front of its travel before each reading is taken. Make a record of these readings. If the TIR is not over 0.13 mm (.005") the engine can be put in approximate alignment to the marine gear without connecting the shaft to the coupling at this time. If the TIR is more than this, use the steps that follow to get the engine in approximate alignment with the transmission. The final alignment reading must be made while the engine and marine transmission are rotated together without rubber blocks (2) installed. Use the indicator on surface (Y) to measure the total end play on the crankshaft. This reading will be needed later in the instruction. (2) Remove all dirt, rust and foreign material from the surfaces on transmission input flange (4), shaft assembly (5) and spacer group (6). Use a file to remove all burrs or damaged areas on the surfaces. Install spacer group (6) and shaft assembly (5) on flange (4) with bolts (7) and the nuts. arrows (8) on spacer (6) must be turned in the same direction, as shown. Loosely install bolts (7). Install bolt (9) through spacer (6) at (X) and tighten it. Tighten bolts (7). (3) Measure