Hard feel to brakes on Defender 90

When I brake hard, the pads grip well ( they are new ) but then the brakes feel hard to the touch and braking goes off as if pads are made of wood ! ( doesn't seem to do it all the time though ). When I fitted the new Ferodo pads, all the caliper pistons pushed back in ( and I have checked there are no leaks ). No pulling to a certain side either and it was doing this before I changed the pads although passed the M.O.T. fine etc ! Brake hoses are Goodridge type. I do intend to fit new front calipers as they are a tad grotty anyway.
I'm no expert on brake servo's but could this be causing the problem ?

Have you checked the servo operation , During engine starting?
Pump brake pedal, until hard, then keeping foot on the pedal start the engine, does the pedal drop slightly?

Cheers

Your on the right track maybe, I'd check first for any vacuum leaks and depending on what provides the vacuum on your vehicle, and the operation of any oneway valves the system will have, that will be plenum and/or servo or both on a V8.

neilly said:

Have you checked the servo operation , During engine starting?
Pump brake pedal, until hard, then keeping foot on the pedal start the engine, does the pedal drop slightly?

Cheers

Click to expand...

Yes, brake pedal very firm with engine off but then goes a very short distance down when engine started.

I've had that feeling like the brakes are very hard and not very effective when my push rod's been wound out a little too far. It's the push rod that sticks out of the servo and bears against the plunger in the master cylinder. If you unbolt the master cylinder there's usually enough flex in the metal pipes to bend it gently away from the servo and you can wind the push rod in a little. You get a bit more slack on the pedal, but better brake feel and less likelihood of binding as the vacuum builds up.