Brake pedal travel

[phorbiuz]

Car in question here is my 1984 Ford Capri 2.8i.

It has developed a new and intermittent problem on the brakes. Once in a while when I press the brake pedal the travel is further than normal and the brakes aren't as strong. If I release and press again they're fine immediately and it might not happen again for another few dozen miles. It's regardless of whether I've just started driving or been out for an hour in it. There's also no obvious fluid loss and at all other times the pedal feels perfectly normal.

99% of the time it's fine, but that 1% could be the problem one day so I want to sort it.

Any suggestions?

[megadethmaniac]

I had exactly the same symptoms on my Uno many moons ago. It turned out to be a sticking rear wheel cylinder, it would retract then intermittently seize in place then go again causing the long peddle travel on occasion.

That would be my first port of call.

[suffolkpete]

Could be the front pads being knocked back, for example by play in the front wheel bearings, so that the next time you apply the brakes they have further to travel.

[Wicksy]

That's a scary one The previous explanations might well give a an increased pedal travel and warrant an urgent inspection check but seized pistons and cylinders usually give uneven braking, causing pulling to the left or right and the syptoms don't come and go, they persist.
My money is on the master cylinder - I had a Jag that did exactly the same as your Capri and I cured it with a new MC. I guess the technical explanation is that the seals wear enough to allow occasional partial failure so the piston has to travel further to compress the fluid.
Don't wait till the pedal goes completely to the floor as that is a distinct possibility IMHO

[Grumpy Northener]

Don't wait till the pedal goes completely to the floor as that is a distinct possibility IMHO

It happened to me !! and it's no fun coming out of blind junction because the pedal has gone to the floor - fortunately nothing was oncoming in my path and I managed to roll the car to a stop but I nearly had trousers that matched the brown seats of the car.

[megadethmaniac]

Any which way, get those wheels off and have a look at whats going on.