I've came across a hydro-boost system,on a 01 chevy 3500, that at low rpm had to low of pressure to operate both the steering and brakes at the same time. I figured it was a simple fix with a pump replacement. The pump was replaced and the problem was better but still there. Steering was just to hard. So I figured that I just got a some what sorry pump and chalked it up as poor quality control on A1 cardones part. So I installed another one from O'Reilly's. Same thing all over again. Now,I'm a fairly level headed person but now I'm pissed. So then I do some Internet searching and find some info on the check valve inside the pump. This was on its adjustment and modifications to increase pressures.
http://westtexasoffroad.homestead.com/p ... ering.html
So I go ahead a pull the check valve out and pull it apart.
Valve assembly
Valve internals
I took it all apart and installed a washer under that small spring in the internals and trimmed the stem like that web page instructed. I reassembled the valve and installed it back in the pump. I filled the pump full of fluid and cranked the truck to see if I did any good. The result was the best power steering I've EVER felt in a newer chevy truck. No tightness anywhere and you could spin the steering wheel with one finger.
One problem with it, it had a little pump noise. Thought it was just air and proceeded to turn it lock to lock to bleed it some more. As I turned the wheel all the way to the left and hit the spot a heard the pump squeal and make a loud POP!!!! Then no more power steering. At this point I am confused and really annoyed. I look under the truck and see a steadied steam of P.S. fluid hitting the ground from the pump body. Yep, I'm doing it all over again and I'm not happy.
Took it down and find this.....
Pop!!!
Not what I wanted to happen.
So I bought another pump and made the same adjustment less the shim under the small spring. Now it works great with no bind,squeal or poping.
Stock setting
Adjustment set from cardone
Adjustment after a get done tightening it.