Had rear ns brake pipe replaced for mot. advisory on discs and pads front replaced those because front brake os started binding and pedal going hard after about 10min of driving, still binding, so replaced flexi and caliper and it's still doing it awaiting new slide pins hoping it those as bottom pin with rubber bush was tight. Anyone else had a similar problem and fixed it?

If your new caliper slide pins don't make any difference, I've read the brake master cylinders can give problems on theses, what year Scudo & does it have ABS?
Did you notice was the rear n/s brake is binding as well?
For safety reasons, the front o/s & rear n/s brakes work as a pair but separately from front n/s & rear o/s brakes which also work as a pair.
I'd imagine both brake cycles should have some sort of recuperation valves in the master cylinder which lets the fluid back into the reservoir when you release the foot pedal.
If the valve for your offending caliper is faulty, this could be a possible culprit?
Also worth checking is the proportioning valve which lets the fluid go to the front o/s & rear n/s brakes, if all the braking is going to the front, maybe a stuck valve?
Somebody correct me if I'm wrong, just throwing a few suggestions out there which might help with your diagnosis, good luck.

Just another thought, when you replaced the rear n/s brake pipe, did you have the back wheel on the ground when you bled the rear brake? The rear brakes have a load sensing proportioning valve which only operates when the rear suspension is in driving position i.e. sitting down under the weight of the van & not jacked up, could still be air in the system.

Rear brake pipe was done by mot station so no idea if they had wheel on ground when bleeding, it's a 05 and haven't noticed any other brake binding , it all started after rear ns pipe was replaced doing all I can my self now then off back to garage as they will only change everything I have done and charge me labour. Will bleed rear brake when rain stops didn't know they were linked .is there a procedure for bleeding?

You should probably bring it back to the garage who did the original work as they're responsible for the eff-up.
Anyway, bleed the rear n/s drum first & then the front o/s brake, might be an easier job if you have a set of ramps to put under the wheels or put the van on an axle stand, remove the rear wheel but jack up the n/s suspension a bit to put it under load.
You'll also see the proportioning valve mounted on top of the rear axle over to the right.
A couple of more checks you could do while you have the front wheel off is slacken the bleed nipple, this will relieve the braking pressure on the front disc. If it spins freely after you do this, you'll know it's not the caliper at fault.
Secondly, when you have everything back together, pump the brakes 4/5 times till the pedal is hard & keep your foot on it. Now start the engine & see if the pedal starts to sink, if it does, this will tell you your servo is working.

Quick update took van into garage who works on these as taxis . He's as stumped as me . Basically front brake piston is not going back (new caliper) ok when bleed nipple open ok when flexi undone when loosens master cylinder bolts ok but when tightened up not. Lot of head scratching ? Still no clearer. Fine when cold but after 10-20 min hard pedal . Will post updates when I get anywhere

I did mention the master cylinders give trouble on the Scudo's, have a read of this article, sounds exactly like your problem. http://mgaguru.com/mgtech/brakes/bt101a.htm
You should pick up a cheap one at a breakers & most will refund your money if it doesn't work.

I agree it all points towards master cylinder but mechanic suspects link from pedal to servo linkage sticking and not allowing master cylinder to return fully but was going to seek advice on how to get to linkages easier as it looks awkward. He's ring me after weekend and I will book it in for master cylinder change but he's adamant it will not solve the problem

If it was the linkage, surely it would sticking all the time & why do they un-stick when you stop driving? When you put your foot on the brake, does the pedal go down a small bit & not return?
I'd say your guy just doesn't fancy the job as it's a pig to change the master cylinder & servo.
Have a read of the comments on this thread https://www.fiatforum.com/scudo/227255-intermittent-loss-brakes-2-ltr-scudo.html

This is another article I came across which is something you could try yourself.
Les Rae, England
Fiat Scudo 2003

The brake pedal on my Fiat Scudo intermittently becomes hard and the brakes are not effective. I have changed the vacuum pump but this has made no difference. Any advice would be appreciated. Can anybody help? (2L jtd)

Answers
I had the same problem with my 2l jtd. I changed the pads, discs, calibers/master cylinder over 2 years. One last try, I took off the master cylinder to expose spindle in servo turned the spindle anti clockwise 2 or 3 times working perfectly ever since easy. Good luck! Alanoc from Ireland

Sorry it's been a while but finally got around to changing master cylinder today, looked at spindle in servo but wouldn't budge and didn't want to snap anything. Brakes haven't been binding as much but pedal has been going hard after about 20min/4miles then after a while freeing up as
Said before and also having brake judder as disc is slightly warped now.right back to topic after changing master cylinder and having been on a test drive brake pedal has been fine and only problem has been judder on motorway so fingers crossed and a new disc all should be sorted . Will reply/post again in a few weeks when I have replaced disc and dine a few more miles, thank you all for your replies and input

Answers
I had the same problem with my 2l jtd. I changed the pads, discs, calibers/master cylinder over 2 years. One last try, I took off the master cylinder to expose spindle in servo turned the spindle anti clockwise 2 or 3 times working perfectly ever since easy. Good luck! Alanoc from Ireland[/QUOTE]

This does work ? hold spindle with mole gripps and turn clockwise as in screw in 2 to 3 turns , which on mine was all way in till wnt turn no more. Works perfect after changing everything and spending money which I don’t need to