Heads up for all R8/10 owners - brakes

Gone

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Over the last few months I've probably dismantled more than 20 R8/10 brake calipers.

All but 2 were correctly assembled. That is, the gap in the self adjuster circlip inside the piston was not alligned with the mark on the front of the piston and that mark was not aligned with the bleed screw. This means that sometime in their life all these calipers have been overhauled and reassembled incorrectly.

If they are not overhauled correctly air is trapped in the system and the pedal is spongy.

If you have one of these cars and you dont have a firm pedal then it is fair to assume air is trapped in the system and if this is still the case after a bleed I would suspect air trapped behind the piston

There is a workaround that does not involve overhauling the caliper.

P
 
I wrote on A/F recently that the marks on my Floride S were so very faint that they were almost illegable. I have only ever seen a drilled dimple before. So if you cannot find the drilled dimple look for a very faint etched line. Oh by the way what is the quick fix work around for future reference.
 
Sorry I was being slack not mysterious.

The self adjuster is a circlip that is compressed slightly when it is pushed into the back of the piston. There is a small gap in that circlip that is supposed to be aligned with the mark on the front of the piston, usually a small drilling.

When the caliper is filled with fluid that gap in the circlip should allow any air behind the circlip to move through the gap and then rise to the top of the caliper chamber, the highest point of which is where the bleed nipple is located.

If you suspect it has not been properly assembled try the following:

Remove the caliper from its bracket as if you were changing the pads.

You are attempting to bring any air trapped behind the self adjuster circlip to the back of the caliper so that when it is remounted that bubble is under the bleed nipple.

With the hose still attached hold the caliper so that the back of the caliper is facing up and parallel to the ground. Imagine the caliper is a clockface. Tilt it so that the 12 o'clock is the highest point then move very slowly to one o'clock, then two, three... and so on all the way back to 12. Remember, you don't know where that gap in the circlip is.

Do this slowly because air bubbles move fairly slowly through brake fluid.

Do this for all brakes.

Bleed brakes.

Did that make sense?

Note: if assembling after a caliper overhaul, prime the caliper with brake fluid. Because you know where the circlip gap is tilt it so that any air finds its way out and fit the bleed nipple and new brake hose (don't be a tightarse, if you're redoing the seals its time for new hoses!!!). There will still be air in the system but it shouldn't be behind the adjuster.

P
 
So simple of course why didn't I think of that.:confused:
 
Sneaky !!!!

Hi P,
And you ask me to help you fix things, and you come up with this. Now I ask you !!!!!!

Ray geckoeng
 
R10 Brakes for my Floride..

I recently fitted R10 brakes to my Floride because the original drum brakes where well and truly shagged and I could not be happier with the results. The standard 4 wheel drum brakes had previously been machined beyond their safe capacity and were out of round, and a real handful to drive.

The new rear brakes fitted straight on and to my delight the master cylinder had already been replaced at some stage and had the necessary perforations in the end cap to allow the fluid return which enables the pads to release from the disc. Even the handbrake bell crank and cables from the R10 fitted straight on.

The front brakes were a different matter…The Floride stub axle was too short to allow the disc setup to work so the whole front suspension was replaced with R10 gear as well. Once again it fitted straight on and works a treat.

The upshot is that I am now confident enough to drive in heavy traffic and throw the old girl into a corner knowing that she will stop as required; another novelty is the handbrake now works properly for the first time in a decade.

The parts were cheap because I bought a pair of old rusted R10s from a paddock in Brisbane and managed to salvage a pretty good set of brakes from the two wrecks. If anyone needs more info on this transformation I will be happy to assist.

Graham
 
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I recently fitted R10 brakes to my Floride because the original drum brakes where well and truly shagged and I could not be happier with the results. The standard 4 wheel drum brakes had previously been machined beyond their safe capacity and were out of round, and a real handful to drive.

The new rear brakes fitted straight on and to my delight the master cylinder had already been replaced at some stage and had the necessary perforations in the end cap to allow the fluid return which enables the pads to release from the disc. Even the handbrake bell crank and cables from the R10 fitted straight on.

The front brakes were a different matter…The Floride stub axle was too short to allow the disc setup to work so the whole front suspension was replaced with R10 gear as well. Once again it fitted straight on and works a treat.

The upshot is that I am now confident enough to drive in heavy traffic and throw the old girl into a corner knowing that she will stop as required; another novelty is the handbrake now works properly for the first time in a decade.

The parts were cheap because I bought a pair of old rusted R10s from a paddock in Brisbane and managed to salvage a pretty good set of brakes from the two wrecks. If anyone needs more info on this transformation I will be happy to assist.

Graham

A bit late to reply to this but.....

Anyway, you could have fitted discs at the front regardless IF you had had early R8 hubs not R10 hubs, since the early R8 (R1130) cars had the same length stub axles as the 4CV-Dauphine-Florides. Or, you could have had the R10 hubs machined to allow the wheel bearing spacing to be reduced to match the earlier short stub axles.

No use to you at all now, and I'm not trying to be a smart**se, but at least someone else might read this who has missed earlier threads on the subject.

Cheers
 
A bit late to reply to this but.....

Anyway, you could have fitted discs at the front regardless IF you had had early R8 hubs not R10 hubs, since the early R8 (R1130) cars had the same length stub axles as the 4CV-Dauphine-Florides. Or, you could have had the R10 hubs machined to allow the wheel bearing spacing to be reduced to match the earlier short stub axles.

No use to you at all now, and I'm not trying to be a smart**se, but at least someone else might read this who has missed earlier threads on the subject.

Cheers

Yes JW of course I know all that now, but at the time I was a mere tadpole just starting out with my first French car.
 
Yes JW of course I know all that now, but at the time I was a mere tadpole just starting out with my first French car.

I thought you did of course. I was posting more for others who might see the thread. I was feeling pretty silly myself, speaking about missing the obvious, about 6 months ago when I discovered that you could machine the later hubs to get the bearing spacing right. I'd been hanging onto precious early-type hubs for years.

Cheers
 
Great information guys. I don't have trouble bleeding my brakes but what I don't get is why I lose a good pedal over say 6 months of the car not being used. It's been at least six months since I drove the little beast last and the pedal is just about to the floor when I try it. I haven't bothered re bleeding yet. When I re register it next, I'll bleed them again at the same time I fit the new brake light switch. Oh, and I'm not losing fluid or anything so I'm a bit miffed as to why they don't stay good.
 
J-man,
You need to rebuild your master cylinder, properly. And I believe the only way to do that is to have it sleeved in Stainless. Or get a new master cylinder. We attempt to refurbish old rusted units, and leave too many imperfections in them. They may work for a while when re-bled, and with a new cup and washer in them, but there is lost tension on the cylinder wall, and as the cup sits for months (or years) without use. You are going to loose the pedal. Re-bleeding will revive the cups and seals for a short time, but you go back to what you had before.

There is only one way, and that is the correct way.

Ray
 
Great information guys. I don't have trouble bleeding my brakes but what I don't get is why I lose a good pedal over say 6 months of the car not being used. It's been at least six months since I drove the little beast last and the pedal is just about to the floor when I try it. I haven't bothered re bleeding yet. When I re register it next, I'll bleed them again at the same time I fit the new brake light switch. Oh, and I'm not losing fluid or anything so I'm a bit miffed as to why they don't stay good.

If you are not using your car for an extended period it pays to go out to the garage/shed once a week and give the brake pedal a few good applications, so as to keep everything free and lubricated. Cars are not designed to sit for extended periods without use. It also pays to start them up regularly as well
 
Thanks Ray and Col, my master cylinder was recond early last year by Power Brakes and was sleeved then. I probably should have mentioned that. The callipers haven't been done in the 10 years I've had it though. Yes, I don't like it sitting there doing nothing either and agree its bad for them but unfortunately my toys have had to be shelved since my wife got sick March last year and has been in and out of hospital since :(
 
My thoughts are with you and your wife.

Ray
 
More on R10 brakes...

Three years ago I converted my o'l Floride brakes to R10 disc brakes and couldn't be happier except some fool, who shall remain nameless, used ordinary axle grease under the caliper boots instead of brake grease.

So one by one the piston rubbers have been swelling and I've had to rebuild them and install new rubber seals. I've been using DOT4 brake fluid instead of DOT3 and wonder if this may have contributed to the rubbers swelling...anyone?:confused:
 
Thanks Ray and Col, my master cylinder was recond early last year by Power Brakes and was sleeved then. I probably should have mentioned that. The callipers haven't been done in the 10 years I've had it though. Yes, I don't like it sitting there doing nothing either and agree its bad for them but unfortunately my toys have had to be shelved since my wife got sick March last year and has been in and out of hospital since :(

Our thoughts are with you too. Best wishes from Perth.

I wonder what rubber seal Power Brakes put into the master cylinder? They know their stuff, or did when I used them when we lived in Adelaide. I'd ask them for their opinion as an aside. I've never found brake problems from leaving a car for a few weeks/months with the right rubber seals and the right fluid.

Does the system pump up with a few vigorous pumps on the pedal? It might be simply a MC piston rubber seal one size too small. Is there ANY leakage out of the back of the MC?

I'd say that even if the thing behaves with more regular use, something isn't quite as it should be. And I think it must be at the master cylinder from what you've described.

As before, very best wishes.
 
Thanks John, appreciate that. I haven't had a close look at the new mc for leaks since fitting it but the level hasn't dropped. Yes, I agree John, I don't think it should lose its pedal just sitting, my 63 XL Futura sat for about 8 years at one stage & the pedal never changed!
 
My Mitsubishi van has sat for 10 years and I recently revived it. Brake fluid level still the same no leaks, and brakes work perfectly. But I will have them rebuilt just to be on the safe side.
 
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