Power steering weak but functional

[Das Delfin]

Hey all, today I went to town on the car and one thing I replaced was the power steering reservoir because I figured the filter was clogged. When I got the car the PS reservoir was completely dry and the car didn't have power steering. I put fluid in and it worked great for two weeks but then became harder to turn. Not as hard as it was before, but there was a noticeable difference in how much effort it took to turn the wheel. I don't have to wrestle it but it's more force than other cars and more force than the two weeks after topping off the reservoir.

I bled it properly 10 turns lock to lock etc. The pump was making a squealing noise but only when it was cold outside. Now it doesn't make a noise anymore.

I would think if the pump failed then I would lose PS completely. It could be a loose pulley belt which I will check tomorrow. I thought it was a clogged filter because I hadn't flushed the old fluid out and it looked pretty nasty. But after draining the system and with a new filter the problem persists. Just wondering if these symptoms make any sense at all and what they might mean. I've searched but haven't found anyone with this exact problem.

Any help would be appreciated.

[turbo55]

I'd check the pulley/belt first, like you said you were already going to do.
If you did have a clog (which I'm not sure what would clog it but let's say there was something), there's a flow restrictor in on of the 3 PS hoses, I believe it's the rack-->reservoir one. If there was a clog, it could be there.
Also, I heard that overtime the hoses can swell up, decreasing the ID. If your hoses are old and leaky, you could replace them. I just did my supply/return hoses, pretty simple job (couple of 2 ft sections of PS hose from Autozone (I know, I know, but NAPA didn't have any in the right size) and some hose clamps).
I'd bet to it being something with the pump though.

[dnguyen1963]

If your reservoir ran dry then you have leaks in your system. Fix that first. PS is operating under high pressure and if the pump cannot get up to pressure then it will be hard to turn.