Bobcat Skidsteer 953 Bucket Won't Lower

We bought a used Bobcat Skidsteer 953 that was leaking hydraulic fluid and the tilt wasn't holding. Took to a mechanic, who said the tilt valve was bad. Replaced the tilt valve, and the leak stopped but the tilt still didn't work. Rebuilt the hydraulic cylinders and everything worked on the drive around. Went to pick it up the next day and the bucket went up but would not lower, and there it sits.

Any ideas?

Thanks in advance.

Bobcat Skidsteer 953 Bucket Won't Lower