Brakes prob, NAC

[Tihol Tiholov]

Haudi gents.
Sorry for NAC but, since the list is a bit slow ...
Patient - 1990 Ford E150 van, under 130K kms on it.
Issue - Intermittently the brake pedal travels longer before brakes catch.
Most of the time pedal travel is normal.
History - 2 years ago a brake line ruptured (rusted through) in the boonies,
literally, and I added water into brake master cyl.  Not nice, but it was
the only liquid I had and it was better than compressing air.  Drove it home
- under  100 kms and flushed the system, no issues for about a year.
Suspect the master cyl. seals and rear drum brake adjustments - not much
experience with this 1, more of a guess.
Any ideas welcome,
Thanks,
Tihol
Audiless for now.