I just installed another new steering gear box as well as new lines. I am familiar with the standard bleeding process. I filled the reservoir and started the truck momentarily. No fluid drained from the reservoir. Started it up and moved the wheel lock to lock several times. No power and still no change in fluid level. I purchased the steering boxes from chip at power steering services and remember that in his instructions it mentioned a check valve when bleeding wasn't working. I can't find those instructions and he is not available on weekends. Anyone know about this or what might be going on with my steering? Thanks in advance.