Hydraulic oil is getting into motor

[Sandman32223]

Ok so i bought this gehl skid loader, i knew it had a leak, we found a broken bolt and replaced it. But now the hydraulic oil is getting into the motor. What could be the issue? Thanks

 

[smithboy]

I bought a Gehl 4635SXT recently as well. I'm no expert, but if you have one with the Deutz engine, it would seem that a likely place for that to happen is at the oil cooler (radiator). The left side cools the engine oil and the right side cools the hydraulic fluid. I haven't carefully examined the way the cooler is built, but it's possible that only a divider separates the two sides. As I said, not an expert, but I just removed my cooler to replace a hydraulic hose. I just don't (yet) see any other place mixing could happen.