460 power steering issue

I changed the filter and hydraulic oil today on my 460 and when I restarted the tractor I noticed the power steering wasn't as easy/free as it should be. I cracked the line on the left side (upper) and moved the steering wheel and fluid came out so I have flow but not as much as it should. I cracked all of the lines from front to back and no difference. Any thing to look for? I cleaned the screen out good but there was not anything pluggin it when I replaced the filter. Thanks.

First pull the plug next to the P/S pressure line and install gauge. Turn the steering wheel to the lock and hold it, and note the pressure. Should be 1100-1500 PSI. A) Gauge fluctuates/oil foamy-it's sucking air someplace. Is it full? B) pressure within specs- look externally for the problem, possibly stiff joints in wide front axle,or steering column u-joints. C) Low pressure- you need to isolate the components to determine if you have a low pressure problem due to by-pass in the steering unit or pump. You will have to fabricate some fittings to put a gauge in the pressure line.You need to have a valve between the gauge and steering unit. Engine idling, slowly close the valve and see if the pressure comes up. Do not spin it shut in case the relief valve is stuck closed. You do not specify if it steered before you changed the oil, But I think the steering would be acceptable in the 900-1000PSI range. (with valve closed). If the pump and related components are tight, it will climb to 1500PSI pretty quick. If the pressure continues to climb above 1500PSI as you close the valve, stop the tractor and service the relief valve. Obviously, if the pump is putting out this kind of pressure, the trouble is most likely in the steering unit. Get a 460-560-660 I-T manual, it will tell you how to service it.

Thanks Fritz, the steering worked before. I had moisture in it and it slimed up the filter. I flushed it once and decided to do it again. After 3 times it is working right.