Disc brakes not performing.

[meldrew]

My special has standard 2cv disc brakes,and weighs the same as a 2cv.

My problem is the braking seems very poor, with all my weight on the brake pedal there is no bite, and braking distance seems poor compared to previous similar cars I have owned.

It has new discs, pads, on front, and new linings on back, there are no brake fluid leaks and the system is well bled with a very firm brake pedal, and all the new items are well bedded in having covered 500 miles.

I have attempted to buy softer greenstuff type pads with no luck, what am I missing?

Anybody had similar problem, or know of better pads than EBC?

Its a 4 wheeler, any advice on how to improve welcome, or is it my right leg becoming more aged.

[administrator]

Hi,
Assuming that you haven't fluffed up the installation of the brake pads, there should be nothing wrong with the 'standard' setup. Something isn't right somewhere!

I can lock all 4 wheels without too much effort, so somethings' gone wrong somewhere. What was the donor car? Is it running LHM? Calipers have been installed the correct way?

Rgrds
Callum

[meldrew]

Donor car is a 1988 Dolly, using LHM fluid. new rear brake cylinders and shoes correctly set up.
Front callipers are original but all pistons move easily with no leaks, [ I assume the right way round, pads slip in from the rear of the car, no spongy feeling, no fluid loss.

Could there be a problem with the master cylinder? I dont know what to check next.

The only improvement I can get is if I pull my heel back and push the pedal more vertically down, but pedal to floor distance is similar to standard 2cv.

[administrator]

Hmm. Sounds all OK. Check the pin where it enters the master cylinder. I've come across one rusted in there before.

Other than that, are you sure that the brake pipes aren't kinked or restricted anywhere - especially the front one? Try loosening the bleed screw on the far caliper. connect a bit of tubing and see how easy/hard it is to pump fluid through.

Also, are the disks and pads clean. A bit of oil on the disks will contaminate the pads.

Other than that, I'm not sure what the problem is. Does the pedal got down to the floor on the first pump, and get harder on the second pump? That suggests rear cylinder boots - a known problem.

Rgrds
C

[notsmartcar]

Assuming the gearbox seals behind the discs haven't let oil on the inside of the disc and the brake pipes are fitted the correct way on to master cylinder if the brake pedal has vertually no movement back off all the rear shoe adjusters one flat the brake pedal may then travel half way down before bite but do the brakes then become more effective

[Jimmy Cooper]

The 64,000 dollar question is, were the brakes any better BEFORE the rebuild or was it poor performance that made you fit all the new bits? I would have started with the pistons jamming. They move OK you say. Next would be a restriction in the feed pipes (kink or dirty fluid). Did you pump all new fluid through?
My "223" will lock the wheels easily if the brake pedal is pushed enthusiastically. Seem very good so you obviously have "an issue" somewhere. Good luck chasing it down.

[Mendip.Wursel]

The disc brakes on my Lomax are rubbish when compared to a modern car..... I just assumed this was normal.
To lock my wheel takes a lot of effort.
Thanks
Kevin

[llanigraham]

The disc brakes on my Lomax are rubbish when compared to a modern car..... I just assumed this was normal.
To lock my wheel takes a lot of effort.
Thanks
Kevin

It will, because your modern car has a nice little servo to increase the power of you pressing the pedal. On the Lomax it is solely your "push" that does it.

[Jimmy Cooper]

Well, the Lomax is so light in body weight that I can lock the wheels VERY easily. Not that hard a push either. A servo would have it seriously in trouble

[namster]

Same here on my pembleton. My lomax was great for braking, locking up quite easily with not much effort. The pembleton less so, ive checked everything and it still requires a pump. I have bled it, but might do a full flush just to make sure there is no air in the system.