From inside (document excerpt):
Parts MANUAL ZERO TURN TRACTOR Model Number RZT 50 w/50 ” Mower Deck Troy-Bilt LLC, P.O. BOX 361131 CLEVELAND, OHIO 44136-0019 PRINTED IN U.S.A. FORM NO. 769-02923 (1/07) FRAME AND FRONT AXLE 1 5 REF. PART NO. NUMBER 1 603-04303C 777I22489 2 703-05829 3 710-0520 4 710-3005 5 712-04065 6 732-0626 7 736-0300 8 738-04058 9 738-04162A 10 756-04129 DESCRIPTION QTY. Frame Assembly . 1 Graphic, Release Lever . 2 Idler Arm, Drive . 1 Screw, Hex Cap, 3/8-16 x 1.5 GR5 3 Screw, Hex Cap, 3/8-16 x 1.25 GR5 1 Nut, Hx Insert Flnge Lck, 3/-16 GrF 4 Spring, Extension, .75 x 5.06 1 Washer, Flat, .408 x .875 x .059 .
1 Spacer, Shoulder, .39 x 1.0 x .7 2 Spacer, Shoulder, .884 x .19 . 1 Pulley, Idler, 4.25 Dia. . 1 8 5 3 10 7 3 9 4 5 6 2 REF. NO. 11 12 13 14 15 DESCRIPTION QTY. Bracket, Castor Wheel . 2 Axle, Front Pivot . 1 Wheel Assembly, 13 x 5-6 2 Tire, 13 x 5-6 2 Screw, Hex Lock, 2 1/2-13 x 1.25 GR5 710-04652 Screw, Hex Cap, 1/2-20 x 7.25 Gr5 2 710-0514 Screw, Hex Cap, 3/8-16 x 1.0 GR5 2 711-04228 Shaft, Axle 1 712-3058 Nut, Hex Insert Lock, 1/2-13 GRB 2 731-05500 Bearing, Flange, 1.0 x 1.246 6 736-0169 Washer, Lock, 3/8 . 2 736-0227 Washer, Flat, .39 x 1.5 x .134 . 2 736-0250 Washer, Flat, 1.0 x 1.75 x .10 2 737-3000 Fitting, Lube, 3/16 Drive 3 750-04775A Spacer, .51 x .75 x 5.825 2 750-04792 Hub, .76 x 1.23 x .92 4 PART NUMBER 603-04370 603-04385 634-04323 734-04255 710-04186
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