TM-9-2815-202-34 Technical Manual for 8V71T Engines for M109 Howitzer Download
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TM9-2815-202-34 (19) Determine quantity of diffuser shims (33) as follows: (a) (b) (c) (d) (e) (f) (9) (h) Place center housing assembly (12) upright with turbine wheel resting on flat surface. Place flat bar (53) across diffuser vanes (54). Measure distance from top of bar (53) to face of thrust collar (38) with depth gage (55). Measure distance from top of bar (53) to face of diffuser vanes (54). Subtract two readings. Difference is height of diffuser vanes above face of thrust collar. Rotate bar (53) 180 degrees and repeat measurements. Results should agree within 0.001 inch. Place impeller (32), blades up, on flat surface and measure height of impeller blades from flat surface. Measure at least 1/8 inch back from blade tip edge. Rotate impeller 180 degrees and repeat measurement. Results should agree within 0.001 inch. NOTE Diffuser shims come in 0.005,0.010, and 0.020 inch thicknesses. (i) Subtract impeller blade tip height from diffuser vane height. Answer is height difference diffuser is higher than impeller blade tips. Add or remove shims (33), as directed in step (18), to attain a height difference of 0.013 to 0.017 inch. Wear heat-resistant gloves when handling heated parts. Metal components will dissipate heat quickly. Burns to personnel will result. 6-51