Great at Lefts

[mtb.rxstar]

Here's an interesting problem that I've noticed on my '83 240, it's great at making left turns but not right turns!?! I can only assume that it's trying to aspire to be a NASCAR pace car, but I feel we should really face the music and just settle for all around performance!

So the real problem is that the power steering works like a champ when turning left, but then does nothing when I steer to the right and so I have to muscle the wheel and carry some momentum around corners to get it to turn. Any ideas on where I should start? It does have proper fluid and the system doesn't appear to have leaks so I'm thinking that fluid just isn't getting the one side of the system and that there's some sort of block in the valves or something. Thanks.