Classic range brake problem

[clairedave]

We have a classic ranger over with VM engine...bled brakes to change fluid...all working ok...been on motorway today and brakes work when first applied then go hard ? Any ideas what can be wrong. Once start driving again they are ok.until braking second time..be glad of any suggestions please

[JIMBOBLY]

have your front calipers got 2 hoses on each caliper,if so,have you bled all 3 nipples on the caliper,usually the top nipple is hard to see,cause it covers over with mud n stuff,just a thought,cause ya problem sounds like there is still air in the system

[Dr Neil]

sounds more like a servo/vacuum pump problem if pedal is going hard. Check vac pipes for leaks and check vac pump.

[dod51e]

My money would be on Servo giving up the ghost.  Air in system will give spongy or no pedal.  The symptons you describe are indicative of a lack of vacuum.  Sure I have a spare knocking around somewhere.

[clairedave]

Found problem it was corroded pipes and they have been replaced...weird as the garage passed its MOT !