Spongy brakes
 

Just had replacement front discs, pads and pipes about 100 miles ago. Today after driving about 20 miles the brakes felt spongy. Some resistance at the top of the pedal but then it gently travels to the floor under a bit of pressure. When fully depressed the brakes hold the car at rest but I am less than sure they will bring the car to a halt when underway. However I managed to drive the car home with very gentle braking, putting the gear into neutral when nearing a junction and slow driving. I can't see the "Min" mark on the fluid reservoir but the fluid is about halfway down the angled shoulder below the vertical filler tube.

Master cylinder or air lock?

If the former, are they easily obtained?

The max level is about halfway down the filler neck of the reservoir, not sure about min. Bearing in mind what you've had done I'd suspect an airlock.

If it does turn out to be a problem with the master cylinder, they are shown no longer available from Rimmers, allegedly All Car Parts Fast has them but I'd take that with a pinch of salt, they have been known to show "ghost" parts. The good news is the same master is fitted to all petrol ZTs and ZT-Ts and 2.5L 75 tourers. See here.

Possibly needs a bleed with a t4 it was the only way I could get a decent pedal after a pipe replacement!:eek:

It doesn't sound like your problem, but be aware that new pads will feel a bit spongy until they have bedded in properly. The pad faces need to be worn to match the discs, before full braking is restored - until then, they will have some springiness when applied.

Oldie's description of the symptoms sounds a bit more than that, I think.
A garage pressure-bleed is the first place to start as 3Disco says, before trying to source (and pay out for) a master cylinder which may well not be needed.

David

I thought similar after replacing the front pads and discs. I was going to have a bleed etc., the following week but as the pads bedded in the pedal improved so I didn't bother. It is now back to normal but it did worry me for a few days.;) As you have replaced the pipes also, I understand that a bleed using the T4 actually works for the abs side to kick in.
Mike

A thank-you to the respondents.

Does anyone know where the minimum fluid level should be? I've attached a sample picture from the internet. The fluid level on mine is below the vertical filler pipe, approximately on a level with the top of the writing. This seems a little low to me. If I decide to top-up: a) what fluid is recommended, and, b) is it ok to mix fluids. The brakes were done by a garage familiar with Rover 75s, but lacking a T4. Perhaps I should have found a T4 user to do the work.

The level needs to be halfway up the neck. Any dot 4 fluid can be used/mixed. Why was it so low? a T4 will do it quicker and better to a degree, but not a must in my experience .

After a lot of image hunting on the internet, the minimum level is just above the join between the top and bottom halves. Not the best photo but you can just about make out the min level marker above the join.

https://c1.staticflickr.com/5/4171/3...afb69bf0_z.jpg

Silly question maybe, but you have checked the all brake callipers/hoses/nipples are dry, not just the ones they replaced, haven't you David?

David