Home>> 8N638 - Hydraulic Pump Safety Valve Hydraulic Pump Safety Valve - Fits ® - 8N638 Sugg. Retail Price: $20.45/EA Out of Stock Quantity: EA Product Details # 8N638 New (Aftermarket Part) Hydraulic Pump Safety Valve Weight: 0.25 lbs Replaces Tractor Part #: 181087M91 Where Used FITS FORD® 8N, 9N, 2N FITS MASSEY FERGUSON® TE20, TO20, TO30 Specifications Instructions Any use of OEM part numbers is for reference only. Need help finding a tractor part? Give us a call at 1-800-462-7335.