RRC 1989 brake issue

Hiya guys, after a little bit of advice if possible.
Been working on my Rangie for a while (MOT work) Had most of the braking system apart at one time or another. Have just got the car finished and bled all the brakes out (as stated in the Haynes laugh a minute manual)
There is no air coming out of any of the bleed nipples, on the calipers, accumulator or booster, very little fluid comes out of the ABS nipple though. it comes out just a very slow dribble.
I get a very good solid pedal. Until I run the ABS pump to bleed the master cylinder. The pump cuts out after about 1minute 15 seconds and it draws a fair amount of fluid from the reservoir. After this when you put your foot on the brake pedal and release you can here a sucking noise from the master cylinder/reservoir. Please note that the fluid level is not going below minimum at any time.
if you leave the car alone for an hour or so all of the fluid has returned to the reservoir.
Does any one have any ideas on this.
Thanks

Have had the experience of bleeding the ABS on my Classic after I changed all the brake pipes. From what you say, the pump running for over a minute means there is something wrong in there. I believe the pump should run for no more than 45 seconds.

If I was pushed, I would suggest it sounds like you may have a problem with the pressure accumulator. I've seen somewhere the pressure accumulator can loose its charge of nitrogen. Be careful, if you can't find any obvious leaks or splits because the system works under high pressures and you could do yourself some damage.

All of that said, it is a pain to bleed the ABS system, I seem to remember I went through about 8 litres of brake fluid doing mine, a pressure bleeder makes life much easier.

Hope that helps ya.

Thanks for the info Kev. Moved the truck today and the brakes are lethal (touch the pedal and nut the steering wheel) although they still have the noise. I'll get hold of a pressure bleed kit and try that sometime though.