4-5 BLADE REPLACEMENT
CAUTION 
WEAR HEAVY WORK GLOVES TO PRO- TECT HANDS FROM SHARP EDGES. WHEN TURNING BLADES, BE AWARE OF OPPOSITE BLADE APPROACHING.
Always replace all (4) blades on an assembly to retain balance. In addition to replacing blades when they become worn and dull, they should also be replaced if the uplift angle on the trailing side of the blade becomes worn off. As the angle wears down, the mulching action deteriorates.
A. Raise cutter using tractor hydraulic system and use transport locks before changing blades.
B. Turn off tractor,set parking brake and remove key.
C. Remove bolt and Belleville washer securing bottom blade to spindle. Remove blade. Shaft wash- er will come off with the blade. (Figure
D. Remove the four 3/8” x 1” capscrews and belleville washers from the upper mulching assembly. Remove mulching assembly. The blade bushing will come off with the mulching assembly.
E. Remove the 3/8” - 24UNF x 7/8” Gr. 8 blade- bolt and nut for each blade. Inspect the blade nut shoulder and the blade bolts for wear. Replace if necessary.
F. When installing new blades on the mulching assembly, make sure that two blades are installed on the top side of the assembly 180° from each other and two on the bottom side of the assembly.
The blades must mount on the rotation “pads” for proper operation. Assemble the (4) new blades to the blade holder using the blade nuts, bolts, and flat- wahsers. Tighten the bolts to 45 ft./lbs. Strike the blade nut with a heavy hammer to seat, then tighten again.
G. Insert the blade bushing in the center of the mulching assembly so that the bushing flange is on the top side of the assembly. Slide the mulching assembly and flanged bushing over the spindle shaft and secure mulching assembly to the upper blade carrier using the (4) 3/8” - 16UNC x 3/4 Gr. 5 bolts and belleville washers. Torque all (4) mulching assembly attaching bolts to 31 ft./lbs.
H. Install the blade washer over the spindle shaft. Install the bottom blade and torque the 1/2” - 20UNF Gr. 8 bolt to 76 ft./lbs. Note: The concave side of the belleville washer must be toward the blades. Do not substitute with a flat washer.
Figure 4-4 MP 6 Blade Arrangement
3/8” - 24UNF x 7/8” Gr. 8 Blade Bolt & Blade Nut
3/8” x 1” Capscrew & |
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| Rotation Pad | |
Belleville Washer |
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Upper Blade Assembly
Bottom Blade Bolt & |
| Shaft Washer |
Belleville Washer |
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