R420S OIL PIPING Parts group R420S J00000 HYDRAULIC OIL LINE (SUCTION) J10000 HYDRAULIC OIL LINE (RETURN) J12000 HYDRAULIC OIL LINE (OIL COOLER) J30000 RETURN FILTER J40000 HIGH PRESSURE OIL LINE J50000 HYDRAULIC OIL LINE (LIFT) J60000 HYDRAULIC OIL LINE (TILT) J70000 HYDRAULIC OIL LINE (S/P) sale parts diagram catalog online construction equipment excavator tractor