D90 1997 300Tdi rear brakes??

I have been working on the rear brakes of my 1997 Tdi300 Defender 90. The rear brakes have caliper, not drums, which are seized and will have to be replaced. OK so far.

The front brake shoes are held in place with two pins that go through holes in the pads and then through the calipers. The rear pads have no holes and are retain by two metal springs under similar pins which go through the caliper alone.

I notice that the outside pads on both rear brakes are quite loose and are rubbing on the wheel shaft (which contains the bearings etc) next to the disc. (On a cart, this shaft would be called the nave but I'm damned if I know what it is called on a 20th century LR!).

Is this caused by wear or has someone fitted the wrong calipers in the past? The new pads seem to be the same as the old ones. The local Land Rover agents tell me a shoulder inside the caliper should stop the pad sliding through, but I can't any evidence of wear to indicate that this shoulder has been worn away -- if indeed there is one. There is, however, evidence of wear next to the brake disc where the pad has been rubbing and I am pretty sure it shouldn't be doing that.

I will be able to examine new hubs and pads tomorrow, but thought some kind soul on here might be able to offer an opinion meantime.

Derry

Reply to
Derry Argue
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The springs under the pins (if it's the old RRC design) are intended to stop the pad rotating in the caliper and doing the sort of damage that you describe. If it is still happening with the springs in place you need to look further. It is possible to machine the disc off the hub (that's the word you're seeking) if not corrected in time!!

Reply to
Dougal

Dougal wrote in news: snipped-for-privacy@eclipse.net.uk:

They are not rotating, merely sliding back and forth in an inwards and outwards direction (parallel to a radius from the hub) inside the calper. Seems like lousy design to me. And, yes, I can see the pad would machine the disc off in time as a groove has been worn on one side!

Thanks for "hub". I should have known that!

Derry

Reply to
Derry Argue

Sounds like the wrong pads have been fitted at some point.

Reply to
SimonJ

"SimonJ" wrote in news:dhs6j6$7o3$ snipped-for-privacy@nwrdmz02.dmz.ncs.ea.ibs-infra.bt.com:

I'm thinking maybe the wrong calipers as the replacement pads are the same as the originals. But I'll find out today and report back.

Derry

Reply to
Derry Argue

Derry Argue wrote in news:3qeqjkFdmloiU1 @individual.net:

Just back from the local LR dealers. By chance, there was a mechanic in the parts department. He confirmed that the calipers wear in a gritty environment.

As the shoulders which retain the pads inside the calipers wear, they allow the brake pad to move inwards against the hub. Don't know if he was kidding, but he asked if the pad had cut through the hub yet! Can't be that ridiculous as there is a groove at least 1/8 inch deep on one side!

So, correct pads, correct calipres -- just another LR design fault.

Derry

Reply to
Derry Argue

Not really a design fault . considering that I look after 100+ Landrovers that use that type of pad I have never seen it happen before.

The time that the pads usually fall out is when the brake disc wears lower than its designed thickness allowing a worn pad to move into he part of the calliper that does not hold it correctly. Then the pad can rub on the hub part of the disc or twist and bend the split pins enough to allow it to fall out.

Measure the thickness of your discs and that might help you.

Reply to
Marc Draper

Marc Draper wrote in news: snipped-for-privacy@mdeng.demon.co.uk:

Considering a deep grove has worn in the caliper just where there should be a shoulder to retain the pad I can't agree with what you say. This is exactly what the mechanic at one of Scotland's biggest Land Rover dealers said I would find when I spoke to him today. He said it was quite a common problem, so it seems you don't agree.

If you read the postings, you'll see nobody said anything about pads falling out or the pins twisting. I very much doubt that the thickness of the discs is below spec. My guess is that they are over 1/2 inch thick. Haynes says "N/A" for disc thickness, whatever that may mean.

Send me your email address and I'll email you the pictures. Or, better still, I'll copy them to an appropriate site -- if there is one.

Derry

Reply to
Derry Argue

You're right, Derry. This is not a disc thickness issue.

The calipers can wear but really only if the pad is allowed to float around. Missing or corroded springs do allow that to happen. With an unworn calliper the springs are a fairy tight fit under the pins. The more wear there is the less effective the springs and so it just gets worse.

You're going to have to make a judgement call as to whether the calliper wear is excessive or not. I'm presuming that the wear groove in the hub is fresh and that contact has not been eliminated by the use of the new pads and springs (were the springs new, too?). Wear that has allowed the pad to move in radially by 2mm is probably as far as you should go - even that may be too much. If there is a definite groove where the pad edges seat and its in the calliper material rather than rust (which is more likely) you're probably on a shopping trip.

Your discs, callipers etc., if I read things correctly, are the same as the old Range Rover. FTC1381 disc - recommended minimum thickness 12mm.

Reply to
Dougal

In message , Derry Argue writes

You are right Derry I do not agree that it is common. But what it does demonstrate is the necessity to replace the spring clips and pins at every pad change. Perhaps that is why I have never seen it in 15years of maintaining LR products because I do exactly that. Even looking through my pipe of scrap callipers none look to be worn as you describe.

Reply to
Marc Draper

Marc Draper wrote in news: snipped-for-privacy@mdeng.demon.co.uk:

Yes, broken/worn springs have obviously allow the pads to oscillate in parallel to the radius of the hub when travelling over rough ground.

Once the calipers were removed, it was easy to see that the wear was so severe that it was possible to slide the pads out from the hub side of the calipers without removing the pins.

From what the mechanic said, sand gets between the edge of the pad and the caliper and the continual movement allowed by damaged springs grinds down the caliper. These seem to be made of softer metal than the pad. This LR was previously used by a gamekeeper and when I first got it, I washed about a ton of sand out of the chassis -- so that might explain it!

The slot (yes, it is a pronounced slot) in the caliper where the pad and caliper surfaces have been rubbing against each other is about 1/4 inch deep!!

Both calipers and all the brake pads have now been replaced with new.

Derry

Reply to
Derry Argue

I'd go along with that - the only time I've seen the pads dropping through is when the springs/pins are broken/missing - a maintence issue not a design flaw I'd say.

Richard

Reply to
beamendsltd

An expense that you don't need I am sure.

From your explanation of the groove.... Would it be possible that once the pads had slid into the groove that they were then held away from the disc and thus prevented from working, at least on the bottom 50% of the pad ?

Reply to
Marc Draper

On or around 3 Oct 2005 17:03:58 GMT, Derry Argue enlightened us thusly:

early front brakes are the same (except 4-pot and larger pads). The spring things under the retaining pins are there to stop the pads moving, and should as has been said be replaced when the pads are changed - generally, you have to buy a fitting kit as well as pads.

I've not seen wear such as you describe on several vehicles (not all LR) which use these calipers. I surmise that it's either been used in a very harsh environment or someone's been cutting corners on the maintenance and not replaced the pad retaining springs. The springs should push down quite noticeably on the pad when fitting them.

Reply to
Austin Shackles

beamendsltd wrote in news:18941b54d% snipped-for-privacy@btconnect.com:

If someone will tell me where I can post the picture I will put one up.

Otherwise it's going to get a bit boring if I keep repeating myself and you guys keep guessing!

Derry

Reply to
Derry Argue

On or around 5 Oct 2005 21:14:51 GMT, Derry Argue enlightened us thusly:

's all part of the fun. However...

try

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Reply to
Austin Shackles

Austin Shackles wrote in news: snipped-for-privacy@4ax.com:

Went to Inverness to buy parts for the D90 again today but this time visited the after market shop (Davidson & MacMillan). The shop owner also confirmed that this type of wear is quite common in LR calipers!!

So either you guys are living a very sheltered life down south (Land Rovers strictly for the school run??) or we hardened Land Roverists up are out on the salt treated snow, then ploughing through the sand, which is particularly hard on brake calipers!!

Pixs will be posted a.s.a.p.

Derry

Reply to
Derry Argue

On or around 6 Oct 2005 15:45:01 GMT, Derry Argue enlightened us thusly:

yebbut, filling things full of sand buggers almost any mechanism. I doubt any design of caliper will cope with that, TBH. And once worn, things can go wrong as you describe. However... if you know you're working in a harsh environment, you should be maintaining it better. Your comment about the amount of sand that you removed is telling, I reckon.

Reply to
Austin Shackles

Email photos to me and I'll put a page on

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-- Mark.

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Reply to
MVP

MVP wrote in news: snipped-for-privacy@4ax.com:

Reply to
Derry Argue

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