Bleedin Brakes...

What order do I bleed the brakes on my atmo... ?

I have been doing the one furthest away from the master cylinder(M.C) first and then the next furthest from the M.C and finally the one nearest to it last.

When I did the last one the bleed nipple screw was in a mess(rounded) so I took it out and put a new one in. Does this mean I will have to bleed the whole system again or can I just bleed this last one ?

Also do I have to bleed the Master Cylinder, abit nervous of this because I don't want to mess the clutch up as it is a joint unit, think I found the bleed screw on the Master cylinder, it is a bigger bleed screw than the brakes. Abit nervous though because does the M.C have a bleed screw for the clutch also... abit 'bleeding 'confused......

When I did the last one the bleed nipple screw was in a mess(rounded) so I took it out and put a new one in. Does this mean I will have to bleed the whole system again or can I just bleed this last one ?

Also do I have to bleed the Master Cylinder, abit nervous of this because I don't want to mess the clutch up as it is a joint unit, think I found the bleed screw on the Master cylinder, it is a bigger bleed screw than the brakes.

To the first point, if you just took it out, and put a new one in, just do that line. and to the second point, unless you actually drained the MC, I would not touch. Just make sure it is topped up, and you have pressed the brake pedal a number of times, to take up the slack having screwed in the rear caliper piston during repair, and gently go for a test drive, to make sure you have not got a soft pedal, but remember if you have changed the discs, it may take a while for the new ones to bed in.

Thanks John- well when I was repairing the handbrake etc, all the fluid did drain out of the brake fluid reservoir (the brake fluid container in the front) and out through the rear brake bleed screw (I loosened it thinking it may make life easier) as I was dissassembling it.

SO - once I put the cam plate back in etc and reassembled the claipher back onto the car I simply filled the empty reservoir up with new fluid and started bleeding it through the brakes starting with the furthest away from the cylinder as explained... Do you think I am ok with this...?

When I found the rounded bleed screw on the front (the last one I was bleeding) I didn't let the reservoir drain when changing it, in fact hardly any fluid escaped as I blocked the bleed screw hole up so the fluid didn't escape--- so far the brakes feel quite solid normal- just got that last one to bleed tomorrow-- well hopefully unless you tell me something different...

all the fluid did drain out of the brake fluid reservoir (the brake fluid container in the front) and out through the rear brake bleed screw

I simply filled the empty reservoir up with new fluid and started bleeding it through the brakes starting with the furthest away from the cylinder as explained... Do you think I am ok with this...?

so far the brakes feel quite solid normal- just got that last one to bleed tomorrow-- well hopefully unless you tell me something different...

I am surprised you say ALL the brake fluid drained out of the reservoir, as this would have taken an awful amount of time. However the clutch should be OK, as it would not have drained its section of the reservoir. Of course the acid test will be, once you have bleed the last one, how the brakes work. If you have a solid pedal, and it stops the car, I suspect all might be well, but be very careful for the first 20miles or so, keep checking them, and if they go soft, rebleed. That is all one can advise without being there, but I must emphasize, take great care when testing.

Just as an aside, many years ago, when I had to do this type of thing, I nicked one of my mum`s plastic knitting needles of the right diameter, and stuck it up the brake line to stop the fluid from running out, it worked for me
The other trick was to remove the reservoir cap, put a piece of plastic bag over the filer hole, and put the cap back. This stops the air going through the vent, which helps to hold the fluid level up whilst the line was disconnected.

John

I am surprised you say ALL the brake fluid drained out of the reservoir, as this would have taken an awful amount of time. However the clutch should be OK, as it would not have drained its section of the reservoir. Of course the acid test will be, once you have bleed the last one, how the brakes work. If you have a solid pedal, and it stops the car, I suspect all might be well, but be very careful for the first 20miles or so, keep checking them, and if they go soft, rebleed. That is all one can advise without being there, but I must emphasize, take great care when testing.

Yes I was too surprised when I looked at the container and it was empty, I had only really opened the bleed screw because I thought it may make the job easier, I.E moving the piston about dismantling etc. Aah, it should be added that I think I pressed the pedal abit and forgot to do the nipple up resulting in a nice pool of fluid under the brake which I saw the next evening. So yes it drained over 24 hours.
Well, good to hear about the clutch- I can only see one bleed screw on the M.Cylinder (visible if you take the wheel off) should I bleed that one last or should I leave well alone and just finish with the last brake (don't want to tempt fate)-
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Questions : Does the Clutch have its own bleed screw on its section of the master cylinder?
Do the Brakes also have a bleed screw on the M.C?
If they both have bleed screws on the M.C -How can you tell the difference between the two? I can only see one so far... what would that be the clutch or brakes ?... thanks again for help... So far they feel as they should- the brakes have always felt very good on the car generally. lets hope they still do

"1" I can only see one bleed screw on the M.Cylinder (visible if you take the wheel off) should I bleed that one last or should I leave well alone and just finish with the last brake (don't want to tempt fate)-

"2" Questions : Does the Clutch have its own bleed screw on its section of the master cylinder?

"3" Do the Brakes also have a bleed screw on the M.C?

"4" If they both have bleed screws on the M.C -How can you tell the difference between the two?

"5" I can only see one so far... what would that be the clutch or brakes ?...

"6" So far they feel as they should- the brakes have always felt very good on the car generally. lets hope they still do

"1" I personally have not come across a bleed screw on a MC. However that does not mean to say there is not one, but as the reservoir is higher than the MC, then any air in the MC will work its way up the pipe to the surface of the fluid, so I would leave well alone, unless someone knows better.

"2" Once again I cannot see the point of one for the above reason, anyway as the reservoir has a division up the middle to mostly seperate the two systems to some degree, when the brake side of the reservoir drained, it would not have affected the clutch section, so once again leave the clutch well alone, but for info there is a bleed screw on the clutch slave cylinder.

"3" See answer to "1"

"4" This question puzzles me. It seems to suggest, as does "2", that the MC`s for clutch and brake are both in the same unit . There are two seperate MC`s. Can you please clarify if I have misunderstood

"5" See "4"

"6" If they feel solid, and they stop the car efficiently, and dont pull to one side or the other, then it is time to go out and road test, with all the precautions I mentioned in my previous post.

John

Yes thanks again- basically it looks like all the questions kinda lead to the same answer- It seems I am treating/ thinking of the brake and clutch as a separate entities but it seems they all work under the same system, i.e the master cylinder.

I think I have got abit confused because of reading other posts on the forum under 'master cylinder' (when I have searched forum)...
for example :

scottydog
Club Member
Clutch and brake hydraulics share the same reservoir and fluid so replacing the fluid affects both systems.

also : Alan Moore
Non Member
Posts: 151
Location: Brisbane Australia

PostPosted: Sat May 31, 2008 2:42 pm Post subject: Reply
The bleed nipple for the clutch is near the bell housing on the right hand side and should also be done when the brakes are bled. As has been stated both clutch and brakes feed from the same reservoir, only the clutch takes its fluid higher up the side of it. Meaning that you will run out of clutch fluid before your brakes do.
_________________

also other posts have confused me somewhat...

Anyway- I will stick with just bleeding the brakes as you are telling me and in the past it has always proved ok and I haven't even considered the workings of the master cylinder etc... bleed nipples clutch or brakes on the MC.. wether they exist or not- ok I will try not to get too bogged down by the info/ technicalities on the master cylinder etc... thanks again

The two systems only share the reservoir .Clutch has a master cylinder on the pedal and a slave on the gearbox .Brake has the ' master ' on the pedal and a balancer for front and rear bias .
There is a bleed pipe from the clutch slave ( top of gearbox ) down to the underside .
Have a look at the parts manual in the tech section on this site p137 onwards ...

It seems I am treating/ thinking of the brake and clutch as a separate entities but it seems they all work under the same system, i.e the master cylinder.

NO.........The Clutch has its own master cylinder linked by a metal pipe to the slave cylinder mounted, as Lee said, on the bell housing, there is a bleed screw on the slave cylinder.
The brake system has got its own independant master cylinder with metal pipes leading to the front calipers, and, via a balancer or brake limiter as renault prefer to call it, metal pipes to the rear calipers.
Now this is where I think the confusion is. feeding these seperate master cylinders, are two flexable pipes coming down from the one common reservoir, which has a divider internally, creating two seperate sections, one feeding the clutch master cylinder, and one feeding the brake master cylinder, via the two flexable pipes. This divider does not come right up to the top inside the reservoir, so when you top up through the one filler, both sections get topped up. If either the brake or the clutch system looses its fluid, the level will drop on both sides, until it reaches the top of the divider, when the system with the leak will continue to drop, leaving the other system without the leak, still functional.
Sorry to be so simplelistic about this, but I feel there is still a bit of confusion in your postings.
John

Sorry to be so simplelistic about this, but I feel there is still a bit of confusion in your postings.
John

yes for sure...

I think if someone could show it to me on the car and explain I would maybe understand... anyway.. thanks again and I will bleed the brakes and hopefully all back to normal.. with hopefully a working handbrake...

thinking of following Tony Smith's line... well for sure he was doing something very different to me.. I am simply (trying) to maintain a standard Alpine...! and finding it hard enough... well, no I shouldn't complain.. the car has been great for 10 years of ownership Have drove the thing all around Europe without any problems really... Just that it takes alot of time and effort for someone like me who is mechanically wanting to learn but 'unskilled', somewhat... thanks again ! I will see how I get on....

Just that it takes alot of time and effort for someone like me who is mechanically wanting to learn :

In my opinion a22, I think you have done remarkably well considering the above. But I think you are making more of it than necessary, and getting confused in the process. But, Hey, dont talk yourself down, dont worry, we have all been there. Remember, you have done a rather trickey job on the hand brake problem, and you have put it together, bled them, and now they work......what`s wrong with that.
Well done

John

Yea thanks-
well sometimes I don't mind working on the alpine- sometimes things go okay and I can manage to do the work without so many issues- well generally it has been like that and have usually managed to do the work.

It is just that oneday I think something bigger will go! Brakes/Headlamp lenses/ blocked fuel filters are onething but I really don't think I could start dismantling the engine when it goes wrong- which it probably will oneday being a 23 year old car!
Yea- I think Alpines like many classics/ sports are really for enthusiasts with the time, skill somewhat, space and maybe the funds to keep them properly, otherwise it seems alot of work.
Well mine is on the market and has been for a while- hopefully a French buyer will show, with plenty of money

Just to put a spanner in the works ... The fluid reservoir has in fact 3 tappings.
One goes to the clutch master cylinder, and two pipes go to the brake's master cylinder. (One goes to the circuit for the front brakes and one goes to the circuit for the rear brakes.)
Also on the brake master cylinder is a bleed nipple. This is not used for bleeding the brakes, but is only there to plug the spare tapping in the cylinder.

The fluid reservoir has in fact 3 tappings.
One goes to the clutch master cylinder, and two pipes go to the brake's master cylinder. (One goes to the circuit for the front brakes and one goes to the circuit for the rear brakes.)

Yes Andrew, quite right, believe it or not, I did realised that after I had posted my explanation, but did not want to confuse a22 any more than I had done already , but it is a point worth making, Thanks.

Regards
John

hi all- yes got the brakes all bled- understanding the master cylinder (or not) seems they are all working nice-

Now the bad news The original problem of why I dismantled them in the first place- a weak handbrake- seems to still be the same! Seems I haven't cured it!

To recap- I found the cam plate had popped out- managed to get it back in and reassemble the brake onto the car thinking that would probably do it Anyway- the otherside seems really strong so at least one side is working.

I will probably not mess with it anymore as I may make things worse even! Would be maybe interesting to see what others make of this problem- oneside working one not- have adjusted it up to about 6 clicks so it is pretty tight- don't want to overtighten it again as I reckon that is what pushed the cam plate out in the first place

Yes looking to make a sale with the car soon as I reckon I spend about 1 month a year working on the thing!