brake bleeding!!!
#1
brake bleeding!!!
dude so i am trying to put in a new master cylinder for the brakes and i am gussing the bleed screw is on the bottom right(the haynes manual is saying its on the left) and im having trouble bleeding it....how do you do it? i bought this stupd little kit at autozone where you are just supposed to push in a tapered piece of plastic, well it didnt work, and then i got a piece of it stuck ine there and had to get it out!!!! please help, i need to at least bleed the master so i could take it to a shop and have them to the rest of the brake stuff(i bought all the parts but i am not sure if i want to do it all because i have never done brakes before............................................ ....................................any tips or parts to buy at the store to help me would be appreciated
#2
Certified Old Fart
Joined: Oct 2004
Posts: 490
Likes: 0
From: Inkerman, On, South of Ottawa, the 2nd coldest Capital in the World
There's 2 other recent threads on brakes:
https://www.rx7club.com/1st-generation-specific-1979-1985-18/suggestion-broke-bleeder-screw-532135/ brake bleeders
https://www.rx7club.com/1st-generation-specific-1979-1985-18/bench-bleeding-new-brake-master-cylinder-532236/ master cylinder
Read them, there's tons of good advice in there about the master cylinder. Just remember, you can't bleed the system unless you can get the bleeders undone without breaking them off. Break them, and most of the time you need to buy a new caliper or wheel cylinder.
Doing the brakes themselves is really not that hard. I did my first set when I was 16, and didn't know a thing. That was almost 30 yrs ago, and I can now easily walk up to any car and change the brakes. Garages charge far too much for brakes. Its one of the easiest places to save yourself some money. Start with the front, as there are less parts in disc brakes. I presume you have rear drums. If so, what you do is remove the parts and lay them out on the ground in the exact postion you took them off. This way you can remember how to put it back together without having to jack up the other side to compare to. Sorry, but I would have to write a small book to walk you through it step by step.
Best bet would be to download the service manual. Here is a link to a thread that tells you where to find it.
https://www.rx7club.com/1st-generation-specific-1979-1985-18/help-fiche-lost-so-am-i-532218/
If money isn't an issue and you break down and get the garage to do it, make sure to tell them to change your brake fluid. That usually costs about $30, and then getting the bleeders open is their problem.
https://www.rx7club.com/1st-generation-specific-1979-1985-18/suggestion-broke-bleeder-screw-532135/ brake bleeders
https://www.rx7club.com/1st-generation-specific-1979-1985-18/bench-bleeding-new-brake-master-cylinder-532236/ master cylinder
Read them, there's tons of good advice in there about the master cylinder. Just remember, you can't bleed the system unless you can get the bleeders undone without breaking them off. Break them, and most of the time you need to buy a new caliper or wheel cylinder.
Doing the brakes themselves is really not that hard. I did my first set when I was 16, and didn't know a thing. That was almost 30 yrs ago, and I can now easily walk up to any car and change the brakes. Garages charge far too much for brakes. Its one of the easiest places to save yourself some money. Start with the front, as there are less parts in disc brakes. I presume you have rear drums. If so, what you do is remove the parts and lay them out on the ground in the exact postion you took them off. This way you can remember how to put it back together without having to jack up the other side to compare to. Sorry, but I would have to write a small book to walk you through it step by step.
Best bet would be to download the service manual. Here is a link to a thread that tells you where to find it.
https://www.rx7club.com/1st-generation-specific-1979-1985-18/help-fiche-lost-so-am-i-532218/
If money isn't an issue and you break down and get the garage to do it, make sure to tell them to change your brake fluid. That usually costs about $30, and then getting the bleeders open is their problem.
#3
tips for bleeding brakes
https://www.rx7club.com/1st-gen-archive-71/brakes-tip-bleeding-brakes-526213/
https://www.rx7club.com/1st-gen-archive-71/brakes-tip-bleeding-brakes-526213/
#4
ok, i did the rears today....dude, its really not that hard i cant believe a ton of people were freaking out about doing brakes(not you guys).....but.......i went to go get my drums resurfaced but i found out they have already been ground past the minimum limit!!! so i adjusted my the little parking brake strut(only place to adjust on a non-sa?) so the drums could fit with my new twice as thick shoes(literally) but now my rear brakes dont work and when i do the parking it stops the wheels but if i push kinda hard on the tire i can get it to move............what should i do, should i go back in and adjust the strut a little, but i have new drums coming in on wednesday or sooner and i will probably need that much space....should i bleed the rears more? please help i need an answer by tom. cause i need the car to drive....thanks everyone
#5
Certified Old Fart
Joined: Oct 2004
Posts: 490
Likes: 0
From: Inkerman, On, South of Ottawa, the 2nd coldest Capital in the World
Without seeing it its hard to say. To be honest, I'm a little afraid to commit to a guess of the diagnoses because of the dangers involved if you screw up your brakes and they fail while driving.
My FB has rear discs, so I've never seen the drums, but most drums have adjusters that turn, and expand the brake shoes outwards. This is a toothed little wheel at the bottom of the drum. I have seen a 1992 Protege, and they had a little lever that wedged tighter and tighter as the brakes wore. It was across the brakes shoes, just under the wheel cylinder. Without seeing what you've got, my ability to tell you how to adjust them is limited.
Best advice I can give you, is normally you adjust the brakes so when you spin the drum, they just BARELY scrape as you spin it. When you pull the drum on and off, you should have to fight just a little to get it over the shoes. When I say BARELY I mean BARELY touch. They will self adjust properly with use. That is the starting point for adjustment.
As far as the brakes not working, it could be a couple of things. You don't mention if the pedal is really low. If so, I would guess the brakes aren't adjusted out enough. If the pedal goes down, but if you pump them, the pedal gets higher, you have air in the lines. (that is 100% certain with that symptom). You didn't mentioned how you bled them, but unless you have some very special tools, YOU MUST HAVE 2 PEOPLE - 1 pumping the pedal, and the other opening and closing the bleeder.
Bleeding: Start with RR. Open bleeder, tell other person push pedal to the floor and hold. Close bleeder. Have person pump the pedal a few times. Repeat until no more air bubbles are coming out of the bleeder. On the last pump, close the bleeder BEFORE the person hits the floor with the pedal. Confirm with the other person that they never got the pedal to the floor. Repeat on the LR, then RF, then LF. Whatever you do, make sure the master cylinder doesn't run out of fluid. After about 3 or maybe 4 pumps, check and fill it again.
Parking brake: Its not unusual for a parking brakes to not hold well as soon as you put new shoes on. They require some break in. However, if the parking brakes handle comes up too far, the parking brake needs to be tightened more. Also, if your drums are glazed (overheated, sort of burnt), the parking brake won't hold well. I wouldn't worry too much about it just yet. If after a week of driving on the new drums, they are still the same, then its the time to have a closer look. Just make sure they work to some degree at this point. Also, they will usually slip if you turn the wheels backwards. If you notice, the front brake material on the shoes should be smaller than on the rear shoe. (Make sure, or you've got the shoes reversed) This is because the shoes actually turn a little, and pinch themselves against the drum when you brake. To be specific, the proper terminology is the shoes WRAP into the drum.
That should get you started....
My FB has rear discs, so I've never seen the drums, but most drums have adjusters that turn, and expand the brake shoes outwards. This is a toothed little wheel at the bottom of the drum. I have seen a 1992 Protege, and they had a little lever that wedged tighter and tighter as the brakes wore. It was across the brakes shoes, just under the wheel cylinder. Without seeing what you've got, my ability to tell you how to adjust them is limited.
Best advice I can give you, is normally you adjust the brakes so when you spin the drum, they just BARELY scrape as you spin it. When you pull the drum on and off, you should have to fight just a little to get it over the shoes. When I say BARELY I mean BARELY touch. They will self adjust properly with use. That is the starting point for adjustment.
As far as the brakes not working, it could be a couple of things. You don't mention if the pedal is really low. If so, I would guess the brakes aren't adjusted out enough. If the pedal goes down, but if you pump them, the pedal gets higher, you have air in the lines. (that is 100% certain with that symptom). You didn't mentioned how you bled them, but unless you have some very special tools, YOU MUST HAVE 2 PEOPLE - 1 pumping the pedal, and the other opening and closing the bleeder.
Bleeding: Start with RR. Open bleeder, tell other person push pedal to the floor and hold. Close bleeder. Have person pump the pedal a few times. Repeat until no more air bubbles are coming out of the bleeder. On the last pump, close the bleeder BEFORE the person hits the floor with the pedal. Confirm with the other person that they never got the pedal to the floor. Repeat on the LR, then RF, then LF. Whatever you do, make sure the master cylinder doesn't run out of fluid. After about 3 or maybe 4 pumps, check and fill it again.
Parking brake: Its not unusual for a parking brakes to not hold well as soon as you put new shoes on. They require some break in. However, if the parking brakes handle comes up too far, the parking brake needs to be tightened more. Also, if your drums are glazed (overheated, sort of burnt), the parking brake won't hold well. I wouldn't worry too much about it just yet. If after a week of driving on the new drums, they are still the same, then its the time to have a closer look. Just make sure they work to some degree at this point. Also, they will usually slip if you turn the wheels backwards. If you notice, the front brake material on the shoes should be smaller than on the rear shoe. (Make sure, or you've got the shoes reversed) This is because the shoes actually turn a little, and pinch themselves against the drum when you brake. To be specific, the proper terminology is the shoes WRAP into the drum.
That should get you started....
#6
ok i got everything done except im getting new drums in a couple days but the rear brakes do work, also my ss line kit had two identical lines for the rear brakes....did they make lines for a rear dis rx7?.....also my brakes seem to work decent, the peddle is not as stiff as i would like but i can bring my car to a stop, im going to rebleed ina couple days to make sure, can i use dot 4 fluid? listen to this....................when the engine is off my deddle has a lot of pressure to it but as soon as the engine fires up the pressure drastically cuts away!!!!! also how freely should the front rotors move?
#7
Best inexpensive fluid is Motorcraft from Ford.
The pressure drop at start up is your brake booster getting vaccum, this is what it should do.
Do the brakes pull evenly when you stop hard, does it feel slow to stop?
Your rear drum brakes were probably overadjusted as aluded to by Whanrow, which is why they didn't stop the drums at first, but as you used them they re seated.
The pressure drop at start up is your brake booster getting vaccum, this is what it should do.
Do the brakes pull evenly when you stop hard, does it feel slow to stop?
Your rear drum brakes were probably overadjusted as aluded to by Whanrow, which is why they didn't stop the drums at first, but as you used them they re seated.
Trending Topics
#8
Certified Old Fart
Joined: Oct 2004
Posts: 490
Likes: 0
From: Inkerman, On, South of Ottawa, the 2nd coldest Capital in the World
Originally Posted by boog
ok i got everything done except im getting new drums in a couple days but the rear brakes do work, also my ss line kit had two identical lines for the rear brakes....did they make lines for a rear dis rx7?.....also my brakes seem to work decent, the peddle is not as stiff as i would like but i can bring my car to a stop, im going to rebleed ina couple days to make sure, can i use dot 4 fluid? listen to this....................when the engine is off my deddle has a lot of pressure to it but as soon as the engine fires up the pressure drastically cuts away!!!!! also how freely should the front rotors move?
The break pedal will be really firm if the car isn't running - normal because of no power (vacum) assist with the engine off.
If you jack the car up, and spin a front wheel, you should just BARELY hear the brake pads dragging on the rotor. If the wheel is at all hard to spin, or there is any resistance, you have a problem - either sliders, or cylinder is seized.
The most imoprtant things you want to look at right now is that the back brakes are working, and that there is no air in the lines. Find some gravel and slam on the brakes and make sure the backs lock up. Make sure the shoes are on right as per my note above. Then you're absolutely sure they're working. The pedal SHOULD NOT rise if you pump the brakes twice. If it rises on the second pump, you have air in the lines.
#9
wow, that tells you how bad my brakes were for half a year, i never knew that was how the booster works. the only reason i asked about the wheel (or rotor) not spinning totally freely was because i put the new bearings in and everything okay but when i was all done it didnt spin as much as the first side i did if i just grabbed the rotor, spun and let go. My brakes work very well, i can come to a stop very quickly. But my brake pedal goes down about two inches i would say(when running) before i can feel the car slowing and about less than an inch from that point is full force pressure. Is that because of my ss lines?...............also. the thing you said about the brake pedal rising after being pumped twice, is that during braking. Is that why i can start coming to a stop and then pump againg real hard and come to screeching halt(very fun) on my poor tires. thanks for the help guys, now i dont know what i am going to do with these two matching rear ss lines.....should i just see if one will fit to my rear drums(that one in the middle) if that works or doesnt work someone can have what's left if they want....
before the brakes were done my car would slide the rear end out to the right on full force braking, and this feels pretty straingt, may be a little off...im going to rebleed this week just to make sure everything is dandy
before the brakes were done my car would slide the rear end out to the right on full force braking, and this feels pretty straingt, may be a little off...im going to rebleed this week just to make sure everything is dandy
#10
Certified Old Fart
Joined: Oct 2004
Posts: 490
Likes: 0
From: Inkerman, On, South of Ottawa, the 2nd coldest Capital in the World
Originally Posted by boog
wow, that tells you how bad my brakes were for half a year, i never knew that was how the booster works. the only reason i asked about the wheel (or rotor) not spinning totally freely was because i put the new bearings in and everything okay but when i was all done it didnt spin as much as the first side i did if i just grabbed the rotor, spun and let go. My brakes work very well, i can come to a stop very quickly. But my brake pedal goes down about two inches i would say(when running) before i can feel the car slowing and about less than an inch from that point is full force pressure. Is that because of my ss lines?...............also. the thing you said about the brake pedal rising after being pumped twice, is that during braking. Is that why i can start coming to a stop and then pump againg real hard and come to screeching halt(very fun) on my poor tires. thanks for the help guys, now i dont know what i am going to do with these two matching rear ss lines.....should i just see if one will fit to my rear drums(that one in the middle) if that works or doesnt work someone can have what's left if they want....
before the brakes were done my car would slide the rear end out to the right on full force braking, and this feels pretty straingt, may be a little off...im going to rebleed this week just to make sure everything is dandy
before the brakes were done my car would slide the rear end out to the right on full force braking, and this feels pretty straingt, may be a little off...im going to rebleed this week just to make sure everything is dandy
Remember the front does at least 60% of the braking. Just because the car stops ok, does not necessarily mean the back brakes are pull their part of the load. that's why I suggested the gravel road - then at least you'd know the back are working.
As far as pumping the pedal goes - if you push on the brakes just sitting in the laneway with the engine running, and lift your foot and push them down again, the pedal SHOULD NOT come up higher. You must pause for a few seconds between tests. You can't just pumpa away and expect the pedal to keep coming up higher. If it does, you have air in the lines. You can also notice this if driving. If you come up to a stop sign, push on the brakes, then lift and push again. It the pedal come up higher - air in lines.
There should be 3 flex lines in the back if you have rear discs. 1 from body to axle, 1 each side from solid line to wheel caliper.
#12
The gravel road is to allow you to lock up the rear brakes without toasting your tires.... Basically you drive along at a decent speed, and lock up all 4 brakes, you will be able to feel/hear the rears lock up on gravel...
(ie. so you can find out if your rear brakes are doing anything...)
(ie. so you can find out if your rear brakes are doing anything...)
#14
The car stepping out under hard braking indicates your front left caliper was working better than your front right.
Check the skid marks left when you test your brakes on gravel to ensure the rears locked. Helps if you're not quite straight when you do this, so you can see the rear marks clearly.
Your pedal shouldn't get more pressure when you pump it during braking, this indicates your vaccum assist may be leaking slightly.
Check the skid marks left when you test your brakes on gravel to ensure the rears locked. Helps if you're not quite straight when you do this, so you can see the rear marks clearly.
Your pedal shouldn't get more pressure when you pump it during braking, this indicates your vaccum assist may be leaking slightly.
#15
this brake stuff is fairly complex, but it is fun...ok, im going to check to make sure my rotors are not too tight, then ill get my new drums on, check skid marks from braking and rebleed the system so i am sure it is perfect.......hopefully me new wheels will go on too.....this week ill take pics and do a rough write up so we can archive this for future people because it was hard to find a good thread for all of this while i was doing this....AND THE HAYNES MANUAL WAS ALMOST NO HELP AT ALL
#16
My Brakes Were Pulsating While Stopping This Morning(you Can Feel It Slightly Through The Pedal)...it Seemed To Be Less Dramatic When Braking While Not Being In Gear...could It Be My New Wheels And Tires? I Cant Think Of What It Would Be
#18
how much should they be torqued...i did the star pattern....i should do the bottom first right, and make sure it sits right and to the top one(bottom to top then left or right like a + shape)....i doubt my rotors are warped, they are spankin new and i didnt notice anything before with stock wheels...but maybe i guess
#19
Certified Old Fart
Joined: Oct 2004
Posts: 490
Likes: 0
From: Inkerman, On, South of Ottawa, the 2nd coldest Capital in the World
Originally Posted by trochoid
A pulsing pedal is from one of 2 causes, the rotors are warped, or the wheels were improperly torqued.
Usually, but not always, if the front rotors are out of round, the steering wheel tends to shake side to side. Usually, if you just feel a pumping motion through the car and not the steering, its the rear brakes that have an issue.
#20
Ok well i found out i torqued the wheels on wrong...scary...but i got that fixed and i loosened up the nuts holding my rotors on, i had them on a little tight................sorry to keep this going but i have another question: from about 20 almost to a complete stop my car kinda bounces up and down, its done it for as long as i can remember but its just a little more prevelant now, what could that be.....also, i can here my front HAWK brake pads crunching/scratching when going slow and braking...even when not braking i can here them a little, but its not like a long noise, it comes in even waves as i go faster, if my caliper is siezed what can i do....also i did brake in the pads according to the box they came in....thanks for all the info guys, ill post pics this weekend
#21
Certified Old Fart
Joined: Oct 2004
Posts: 490
Likes: 0
From: Inkerman, On, South of Ottawa, the 2nd coldest Capital in the World
Is the "bouncing" seem to be from the front or back? If back, I'd be checking the u-joints. If front, (I'm guessing at this one), tire gone out of round or broken belt in tire?
As far as the pads, I have no experience with those pads, but in general, they may do that for a day or so, but should stop after that. If they don't, the new pads are either adjusted too tight, or the sliders on the caliper are seized or the hydraulic cylinder in the caliper is siezed and is not pulling back as it should. Start with the sliders. Remove the bottom one, flip up the caliper and remove the pads. Put the caliper back into position. You should be able to easily slide the caliper back and forth. If you can't, the slider pins are seized/corroded.
As far as the pads, I have no experience with those pads, but in general, they may do that for a day or so, but should stop after that. If they don't, the new pads are either adjusted too tight, or the sliders on the caliper are seized or the hydraulic cylinder in the caliper is siezed and is not pulling back as it should. Start with the sliders. Remove the bottom one, flip up the caliper and remove the pads. Put the caliper back into position. You should be able to easily slide the caliper back and forth. If you can't, the slider pins are seized/corroded.
#22
it is the front, tires are new tho....grunt.....yeah so the cruching i heard was my brand new caliper scraping the inside of my brand new wheel!!! not a big deal looks wise but scary, the top attaching bolt flew off!! everything is good now except the bouncing....what is out of round?
#23
Certified Old Fart
Joined: Oct 2004
Posts: 490
Likes: 0
From: Inkerman, On, South of Ottawa, the 2nd coldest Capital in the World
Originally Posted by boog
it is the front, tires are new tho....grunt.....yeah so the cruching i heard was my brand new caliper scraping the inside of my brand new wheel!!! not a big deal looks wise but scary, the top attaching bolt flew off!! everything is good now except the bouncing....what is out of round?
Also, what bolt flew off? Any bolt flying off on brakes is NOT A GOOD THING. The rim should not rub on the caliper under ANY circumstances. If these wheels are rubbing on the caliper, you need to get this addressed ASAP. The "bouncing" could be every time the rim goes around and hits the caliper.
"Out of round"; sometimes when tires are made they are defective and aren't exactly round. This happens much less than it used to (in fact I can't remember the last time I had one). Also, some tires are defective in their manufacture and simply can't be balanced. This is also rare nowadays.
Which brings me to another question - you did balance the new tires and rims correct? Either way, #1 priority - get those rims so they don't rub on anything, even if it means going back to your old rims.
#24
The top attaching bolt flew off, this is not good. Do you mean the upper 14mm retaining bolt on the caliper came undone enough to come out altogether, if this is so i strongly suspect you didn't have it located correctly when you tightened the bolt, this is very bad. Check the bolt and threads for damage before replacing it. you may want to use some loctite to ensure it doesn't back out again and check the other side also.
Now check your pads for uneven wear, if they were half off the rotor they will be very uneven, you can even them out but make sure its done very flat to the rotor face. Any high or low spots will lessen your braking.
Are you aware of how your brakes actually stop your car, it is the heat from the friction causing a reaction with the brake compound which coats the rotor and this is what gives the stopping ability. When they are uneven, or out of alignment as I suspect yours were, they will make and uneven coating and cause a pulsing effect, this is what is incorrectly called warped rotors. It is actually an uneven coating on top of the rotor face.
Please do one thing for me when you have this back together, jack up each end of the car and test each corner manually, spin the wheel and then have someone brake, this isn't a stress test but will indicate that that brake is actually moving and grabbing the rotor or drum.
Now check your pads for uneven wear, if they were half off the rotor they will be very uneven, you can even them out but make sure its done very flat to the rotor face. Any high or low spots will lessen your braking.
Are you aware of how your brakes actually stop your car, it is the heat from the friction causing a reaction with the brake compound which coats the rotor and this is what gives the stopping ability. When they are uneven, or out of alignment as I suspect yours were, they will make and uneven coating and cause a pulsing effect, this is what is incorrectly called warped rotors. It is actually an uneven coating on top of the rotor face.
Please do one thing for me when you have this back together, jack up each end of the car and test each corner manually, spin the wheel and then have someone brake, this isn't a stress test but will indicate that that brake is actually moving and grabbing the rotor or drum.
#25
i will, thanks dude...yeah it was very scary, and i am buying some loctite for sure...thanks for all the help i really appreciate it, everything seems ok now but i will make doubly for sure...but i still cant figure out if my rear or my front is bouncing at 20 mph...