Outer Limits 4x4 Board

Hey there tried this in the nissan section with no luck so maybe some more here. I have fitted power steering to my MQ patrol and have a slight problem with it. I have full power assist when turning left but none when turning right. All oil galleries are clear and all new o rings fitted. Manual says internal oil leak. Any ideas where.

I can only assume the manual means on the piston inside the box since the pump doesn't know which way you are turning.
sorry no help here.
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