Very Frustrating Power Steering...Help Needed !!!

Hello
I have been trawling every website on the net and phoned garage after garage and everyone seems baffled by my power steering.
The bearing went on the pump a month ago, I replaced the pump with a brand new one, bled it to death and had intermittent power steering, then power steering that only worked when I revved up the engine and then no power steering at all, and that's the way it stayed.
The belt is tight, fluid level right, system bled etc
I replaced the steering box today with a used one that was definitely working and still I have no power steering. Fluid spurts out of the bleed screw on the box which would suggest the pump is working, but still no power, I can't keep chucking money at it and time I don't have.
Any help would be much appreciated.
Cheers in advance.

If youve done the pump, and the box, then the only thing left are the pipes.

Are you sure there's no issue with them? Blockage, on wrong way arround (if that's possible?) etc?

I think you ought to test pressure on delivery pipe from pump it could be faulty or because you connected it to power steering box after other pump failed you could get some metal swaf traped under pressure relief valve which I think is in pump does pump get noisey not very likely but you may hive a high pressure pipe collapsing internely when under pressure

Cheers for the replies so far.
The pump isn't noisy at all and the fluid seems to flow round the system ok when bleeding.
I don't see it being the new pump as its spurting out of the bleed valve when bleeding (if I open it enough).
So you reckon that maybe I should remove and replace the pipes and hoses, or just remove and clean out.

It self bleeds
Check the pressures as it's sounding a bit Pete tonge

I seem to remember reading about a member who had trouble with either power steering or ACE and it was eventually traced to a partial blockage in one of the pipes due to FOD, Foreign Object Debris.

I'm going to spend an hour or so tomorrow removing pipes and trying to clear them, maybe I'll have some luck.
Tell you what though I'm completely baffled and getting more and more frustrated by the minute.
I'm gonna have arms like Arnold Swarzenegger if I don't fix this soon, two weeks of no power so far and it's my daily driver as well as Lake District green laner !!!
Cheers for the comments so far, all help is much appreciated.

if you can set it up you could take hp pipe out of box screw gauge on to it other side of gauge fit hand valve on other side of hand valve screw in pipe and put end in to power steering reservoir start engine see what flow you have then slowly start to close hand valve and see what pressure you can get don't go above 800psi if you can set it up you will prove pump and hp pipe are ok also youcould have bits of rubber breaking off in side of pips and blocking valves etc have you checked filter if fitted to see what sort od debries are loged in it

I'm struggling a bit because I don't have a gauge of such like.
Over the next few days my plan was to remove each pipe in turn, blow through with air to try and cleans my debris out and refit, I'll the refil reservoir and test it out, I'll just go through each pipe in turn and see what (if anything) happens.
I had a huge row with the guys bought the pump off as they insisted it couldn't be the pump, well now we know it's not the box either, so fingers crossed its a blocked pipe.

Absolutely...I will post back with the results of my pipe testing tomorrow. I'm just gonna be chuffed to get some power back eventually !!!!
Fingers crossed eh !!!

you could try jacking one whee off ground let other wheel rest not to heavly on ground now try steering is there any assistance at all if no luck with pipes could you take off pump and ask supplier if they can test it or do you have a mate who might be willing to swap pumps to prove that your pump is ok

Pump supplier isn't local so it makes swapping it difficult, finances are also an issue as I can't afford to be replacing stuff willy nilly.

I may in fact try to jack up a wheel as you suggested and see what happens,

It's all a bit weird but I'll get there with the right advice.

All very much appreciated.

hi wilfie if all else has failed ,ihave never tried this you could take hp pipe out of steering box add length of rubber or plastic house enough to reach resovior put funnel in top of resovior hold hp pipe start engine with mole grips slowly start sqeezing hp pipe on rubber section if good pressure iwould expect engine to slow slightly if squeezed a lot you should hear release valve making noise I have never tried this as always had axces to gauge I know this is not good for pipe but it might prove something wish I was closer would love to help when taking hp pipe out of box you will have to put blankink plug inbox you might have flow of oil but do you have pressure? you should get about 350to450psi on tick over by putting pibe in funnel you should be abel to watch flow as you slowly start to restrict it