Family owns a 1980 IH 686. During the recent cold snap in Indiana we noticed the hydraulics weren't working. My dad thought water had gotten in the hydraulic line and frozen, so he decided to change the hydraulic oil. We did so. But after running the tractor about 15 minutes the new oil began to gush out of a small hole under the battery. The hole is supposed to be there from what I can tell. Every subsequent time I've used the tractor the same thing has happened and now the tractor is almost out of oil and having is very hard to steer. Any thoughts on what went wrong and what can be done to fix it?