Really the question needs to be asked did they work prior or just recently stop working. Typically hydraulic system works if the following conditions are met. 1. Sufficient hydraulic fluid. 2. Clean filter 3. Working pump Now with that being said if there is fluid leak on low pressure side it will introduce air into the system. Compressing air results in poor hydraulic performance slow or jerky. Lastly water in the hydraulic fluid is even worse causing more issues. I just purchased IH 504 and its previous owner never changed hydraulic filter so when unit ran it whined loudly. Once changed hydraulic pump quiet down and worked as expected. Look for the obvious as your troubleshooting the ford 2000.