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It is important to have the control valve handle and quadrant stops adjusted before mounting pump in tractor. Adjust as follows:
1. Adjust handle to lay half way between quadrant adjusting capscrews when handle is in the "Hold" position. Adjustment is made by removing pump
pulley and loosening the three self locking lever adjusting capscrews. Move pump mounting bracket on adjusting capscrews to relocate lever "Hold" position. Retighten adjusting capscrews securely.
2. Adjust quadrant stops to hold lever in "Float" position. To "float", lever must be held all the way to position "A" or "B". When adjusting, loosen quadrant adjusting capscrews and move lever to position "A". Move quadrant stop to hold lever in this position. Move lever to position "B" and adjust the other quadrant stop to hold lever at position "B".
Retighten quadrant adjusting capscrews. Quadrant stops should hold lever in the extreme position in either direction for "Float".
[Source: Allis-Chalmers publication, Form No. TM-431, included in B-12 Owners Manual courtesy of Mark Waite & Joel Wicker]