RK 55HC,ym1700, NH7610S, Ford 8N, 2N, NAA, 660, 850 x2, 541, 950, 941D, 951, 2000, 3000, 4000, 4600, 5000, 740, IH 'C' 'H', CUB, John Deere 'B', allis 'G', case VAC
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3000's were built using both inline and rotary injection pumps. The o-rings sealing the throttle and shutoff shafts on the rotary pump can be changed, possibly without removing the pump from the tractor. Shaft seals on the inline pumps are not so straightforward.