Bendix Brakes

[Robbersdog]

Hi ,

Ihave a ZX that is fitted with Bendix brakes, problem is I cannot get a decent pedal on it . Pedal will travel to nearly to the floor before working . I've changed the front pads and discs , the back shoes and drums also the master cylynder nothing seems to work. the front pads got very hot at the outset but we stopped about every five miles to let them cool and after about 40 miles they were ok . I've bled the system several times according to the Haynes manual but no luck. Is there anybody out there who can help

Robbersdog

[Guest Colin Hunter]

Hi There.

 

This sounds like a fluid displacement problem to me. It's likely that the rear brakes are out of adjustment and require a large amount of fluid to bring the pistons out to the point where the shoes contact the drum. The brake pressure will then rise and the brakes work.

 

Make sure that the adjuster bars are correctly fitted and that the handbrake cables are adjusted properly. I had a similar problem on my son's ZX and discovered that the adjuster bars had been incorrectly fitted (Girling) and were adjusting the shoes off rather than on.

 

Cheers. Hope this helps. :unsure:

[Robbersdog]

Hi There.

 

This sounds like a fluid displacement problem to me. It's likely that the rear brakes are out of adjustment and require a large amount of fluid to bring the pistons out to the point where the shoes contact the drum. The brake pressure will then rise and the brakes work.

 

Make sure that the adjuster bars are correctly fitted and that the handbrake cables are adjusted properly. I had a similar problem on my son's ZX and discovered that the adjuster bars had been incorrectly fitted (Girling) and were adjusting the shoes off rather than on.

 

Cheers. Hope this helps. :rolleyes:

[Robbersdog]

Hi Colin,

Thanks for the reply. I have read your previous post dealing with your son's ZX . I'll have a look at the adjusters as you advised. The whole story is that the car has belonged to my son for the last 6 years and I replaced all the brake components after he had run the car for 1 year and complained about soft spongy brake pedal . After I completed the work the brakes were a little better and good enough to pass the MOT but I don't think it will any more. I'm wondering if there could be an ongoing problem with the servo unit . I think that may be my next move after looking at the adjusters

Thanks again

Robbersdog

[Guest Colin Hunter]

Hello again.

 

A good way to test if the servo is working ok is to operate the brake pedal with the engine off until you have exhausted all the vaccuum from the system. Then, with your foot still on the brake pedal with normal braking pressure, start the engine. You should feel the pedal go away from you as the vaccuum is restored.

 

To be honest, the Bendix callipers fitted to 1.1s 1.4s and the 1.9d aren't the greatest. They are marginal at best and need to be in good condition to work as they should. I noticed a BIG difference after I overhauled the callipers (new seals & boots ) and replaced the discs & pads. I don't know if it's a ZX thing, but the pedal on ours, although good enough, isn't as firm as the one in the Picasso and also has more travel than the newer car. The Brakes seem to do the job OK though and were well in excess of MOT requirements.

 

Another thought, have you checked the hoses aren't "ballooning" when the brakes are applied? Worst case scenario is that one may be about to fail. Unlikely, but possible.

 

Cheers. Happy tinkering! :rolleyes:

[kfk]

Some thing else worth checking:

 

If the front brakes ahave been binding they may have over heatd the discs, i have seen situations where the brakes are bled and everything is working correctly but the discs are 'dished'.

 

As well as checking runout i would remove the disc and check using a straight edge (steel rule on its side) from one side of the disc across to the other and see if it looks flat.

ie it looks like '|[' and not like '|(' or '|)'

[Robbersdog]

Hi ,

Ihave a ZX that is fitted with Bendix brakes, problem is I cannot get a decent pedal on it . Pedal will travel to nearly to the floor before working . I've changed the front pads and discs , the back shoes and drums also the master cylynder nothing seems to work. the front pads got very hot at the outset but we stopped about every five miles to let them cool and after about 40 miles they were ok . I've bled the system several times according to the Haynes manual but no luck. Is there anybody out there who can help

Robbersdog

[Robbersdog]

Some thing else worth checking:

 

If the front brakes ahave been binding they may have over heatd the discs, i have seen situations where the brakes are bled and everything is working correctly but the discs are 'dished'.

 

As well as checking runout i would remove the disc and check using a straight edge (steel rule on its side) from one side of the disc across to the other and see if it looks flat.

ie it looks like '|[' and not like '|(' or '|)'

 

Thanks Chaps,

Just got back and sorted problem . It was as you said Colin the back brakes were having problems with the adjusters , renewed drums shoes and cylynders now brakes are fine . Just gotta figure out how to renew outer CV boot on drivers side an we'll be back in business . Any suggestions would be welcome

Robbersdog

[Guest Colin Hunter]

If it's a 1.9D the outer CV joints can be driven off the shaft with a sharp tap at the back once the boot has been removed and slid back. If it's a 1.4 petrol the joint is part of the shaft so you'll need either the stretchy type that you slide on with a spreader thingy, or the split "Sticky boot" type that you put over the shaft, away from the joint so as not to contaminate it, then glue the mating faces together with the supplied adhesive. I have heard various stories about both types, but, basically they either work or they don't. Another way is to dismantle the inner joint and slide it on from that end. Another alternative is, of course, a new shaft. I renewed the (Nearside ) shaft on our 1.4 rather than mess with the boot, especially as the joint was already"clicking" on full lock before the boot went. It was £65 exchange against £20 for a boot kit. No contest really!

 

Cheers. Hope this helps. :lol:

[Robbersdog]

Hi Colin,

We did have a Haynes manual but have miss placed it. It looks like I shall have to take the long shaft out . I remember I have to take the the hub nut off , remove the 3 special bolts at the base of the leg and take the steering link off also remove the caliper. Then I believe I have to release 2 bolts that hold the centre bearing in , then I believe the shaft can be removed with a little persuasion. I have found a boot that will replace the broken one however I can't remember what to do next ie how do I split the shaft in order to slide the boot on . would be glad of a little help cos we live in a slightly isolated region of france and there ain't much help close by

 

Hope you can help

Robbersdog

[Robbersdog]

Sorry Colin I didn't read the first part of your last post but that answers my question

Cheers mate

Robbersdog

[Robbersdog]

Sorry Colin I didn't read the first part of your last post but that answers my question

Cheers mate

Robbersdog

[Guest FRANK J]

Hi There.

 

This sounds like a fluid displacement problem to me. It's likely that the rear brakes are out of adjustment and require a large amount of fluid to bring the pistons out to the point where the shoes contact the drum. The brake pressure will then rise and the brakes work.

 

Make sure that the adjuster bars are correctly fitted and that the handbrake cables are adjusted properly. I had a similar problem on my son's ZX and discovered that the adjuster bars had been incorrectly fitted (Girling) and were adjusting the shoes off rather than on.

 

Cheers. Hope this helps. :lol:

 

Hi Colin

 

Perhaps you can help a fellow Scot before ma heed blows up - K reg ZX 1.9 TD - brake problem - suicidally little braking power - is this system particularly hard to bleed??? Pedal goes to floor like no fluid in system or bad master cylinder problem - pumping pedal gives some but little pedal but feels spongy and even full leg pressure gives little braking. If only the spongy symptom was shown I would have thought the servo vacuum was not working. However I have tried 3 different scrap yard servos with no joy. I have also done the following:-

 

-fitted two ex scrapyard calipers

-checked front discs for distortion

-checked front pads for wear

-changed brake fluid

-looked for fluid leaks

-fitted brand new master cylinder

-fitted brand new front rubber brake hoses

-fitted brand new front brake pipe (one side only)

-fitted brand new rear brake cylinders

-fitted brand new rear brake shoe adjusters (and i know that they are right and left handed)

-I have tried bleeding the system

 

Have i gone mad!! Can it be that there is still air in the system after bleeding the system so many times???

 

I will try and make sure that the rear break shoes are adjusted next as you have pointed out above. I will recheck to make sure the calipers move properly. I must say that the handbrake is very good.

I am now lost for words - HELP MA BOB

 

Frank J