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-   -   Bleeding Brakes (https://www.nopistons.com/3rd-generation-specific-18/bleeding-brakes-24054/)

Razerx 09-03-2003 09:49 PM

Ok, i changed to Motul, changed the rotors, new pads, and stainless steel breaklines.



I have bleed the breaks at each corner, went through 2 bottles of motul and know i got all the old fluid out. but my breaks don't feel spongy, but if push the brake petal once, and then again the second push is much harder. Typically this means air, but i can't find it or get it out.



ideas? https://www.nopistons.com/forums/pub...R#>/unsure.png

mazdadrifter 09-03-2003 09:58 PM

there is a specific order in which you should bleed them (start with farthes from resiovar, end with closest (RR,LR,FR,FL) also with all of that work your doing, speed bleeders are like 5 bucks a piece and are worth their weight in gold if you do racing. Just crack them, and pump (ball bearing operated, so it won't let air back in)



Other than that, ummmm, could be a master cylinder?? I doubt it would do that tho.

rfreeman27 09-03-2003 10:19 PM


Originally Posted by mazdadrifter' date='Sep 3 2003, 10:58 PM
there is a specific order in which you should bleed them (start with farthes from resiovar, end with closest (RR,LR,FR,FL) also with all of that work your doing, speed bleeders are like 5 bucks a piece and are worth their weight in gold if you do racing. Just crack them, and pump (ball bearing operated, so it won't let air back in)



Other than that, ummmm, could be a master cylinder?? I doubt it would do that tho.

what he said.



How much fluid did you let out when you were changing the lines?

amp 09-03-2003 10:24 PM

i dont recommend motul for street applications..

tendency to absorb moisture requires you to change the fluid more often than the standard dot fluids....

jspecracer7 09-03-2003 10:35 PM

I agree with Amp...Dot 3 is suffecient.

qwester007 09-03-2003 11:32 PM

My first time at Sebring, my brakes (stock then) began to fade as early as lap 3. If you take it to the track occasionally- Dot 3 boils much too fast.

toddp31 09-04-2003 03:51 AM

If the master cylinder drains all the way down somtimes it ruins the seal, then you have to overhaul it.

turbovr6 09-04-2003 06:09 AM


Originally Posted by Razerx' date='Sep 3 2003, 09:49 PM
Ok, i changed to Motul, changed the rotors, new pads, and stainless steel breaklines.



I have bleed the breaks at each corner, went through 2 bottles of motul and know i got all the old fluid out. but my breaks don't feel spongy, but if push the brake petal once, and then again the second push is much harder. Typically this means air, but i can't find it or get it out.



ideas? https://www.nopistons.com/forums/pub...R#>/unsure.png

Sorry man but you are waaaaay wrong. you have your ideas confused.

When you bleed the brakes you want a nice hard pedal. if you had air, the pedal would be easy to push down, not hard.

jwhite94RX7 09-04-2003 09:43 AM


Originally Posted by mazdadrifter' date='Sep 3 2003, 08:58 PM
there is a specific order in which you should bleed them (start with farthes from resiovar, end with closest (RR,LR,FR,FL) ...

Actually that's wrong (though I doubt that it's the cause of Razerx's problem). The correct order is RR, LR, FL, FR.



Note the numbers in the picture at the top of page P-7 of the shop manual. The reason that FL is further from the MC than FR is that the line for FL goes up near the MC but then goes across to the ABS (on the right) and back again. FR goes directly to the ABS and then over to the MC, so it's the shortest.

Razerx 09-04-2003 05:02 PM

Thanks for info, i will try the right sequence.



As for some of the questions.

I bleed, about a 1/4 of a QT through each point, after i started seeing the clean/new fluid.



the MC has never been low.



As i said it does seem to have the tendancies of a little air, but with all that i bleed, and not seeing a single bubble for a long time. Any chance of getting a bubble in the brake booster, that doesn't flow out to the calipers?

Stang94GT 09-04-2003 05:37 PM

I concur with jwhite -- it's difficult to fully understand what you're saying razerx, but you WANT a hard pedal. The first time you push the pedal it should go down maybe halfway. The second and third time it should move very little to not at all. This is an indication that there is little to NO air in the system. If you could keep pumping the pedal then you would have a leak or massive amounts of air in your system. The only time the pedal should always go to the floor is if your engine is running, I assume you're bleeding and checking your system with the engine off.

Razerx 09-04-2003 06:52 PM


Originally Posted by Stang94GT' date='Sep 4 2003, 02:37 PM
I concur with jwhite -- it's difficult to fully understand what you're saying razerx, but you WANT a hard pedal. The first time you push the pedal it should go down maybe halfway. The second and third time it should move very little to not at all. This is an indication that there is little to NO air in the system. If you could keep pumping the pedal then you would have a leak or massive amounts of air in your system. The only time the pedal should always go to the floor is if your engine is running, I assume you're bleeding and checking your system with the engine off.

sorry was typing fast before a meeting.



My pedal does as you explained, about half way on the first push, an d also no movement on the second.



Perhaps i am just paranoid, but i thought the pedal should be really firm on the first push, not the second. Becuase my car was on jack stands for almost 2 months, maybe i forgot what was 'normal', and you work on something like brakes, you pay more attention to it after you are done.



So if it is normal for the pedal to travel some on the first push and get really firm on the second, my car is fine.

Stang94GT 09-04-2003 09:11 PM

Yup, it's fine - go out and hammer on them some https://www.nopistons.com/forums/pub...IR#>/smile.png

mazdadrifter 09-04-2003 11:16 PM


Originally Posted by jwhite94RX7' date='Sep 4 2003, 06:43 AM
Actually that's wrong (though I doubt that it's the cause of Razerx's problem). The correct order is RR, LR, FL, FR.



Note the numbers in the picture at the top of page P-7 of the shop manual. The reason that FL is further from the MC than FR is that the line for FL goes up near the MC but then goes across to the ABS (on the right) and back again. FR goes directly to the ABS and then over to the MC, so it's the shortest.

well it's right for me, I drive a fc w/o abs

Jims5543 09-04-2003 11:31 PM


Originally Posted by qwester007' date='Sep 3 2003, 11:32 PM
My first time at Sebring, my brakes (stock then) began to fade as early as lap 3. If you take it to the track occasionally- Dot 3 boils much too fast.

Always bleed your brakes before a track event.



I go to the local Ford dealership and buy Heavy Duty Truck Brake Fluid it has a wet boiling point of 365°. I also switch my regular front Hawk Pads to Hawk HP Plus pads. You might want to try that brake fluid.



I did a Chin Motorsports event a Moroso (doing another in Dec.) and never once had any problems with fade all day long.

Razerx 09-05-2003 01:12 AM

before a bleed them a second time, i went parking lot running w/ a M3, and Honda 2000, afterwards my Hawk HPS pads were smoking in the front. Hopefully my new bleed job will help. reason i say that is if you have air in the line it can cause the pads to drag more, when you are off the brake

lane_change 09-05-2003 02:09 AM

How exactly are you bleeding your brakes? You said a 1/4 qt at each corner? That seems like way too much fluid for each wheel.



Just pump the brake a few times, then hold it down. Then have someone crack the bleeder and let the system bleed until it is all fluid. The pedal should fall to the floor during this part of the procedure. Then close the bleeder, release the pedal, and repeat until no air comes out. Then move to the next wheel.



The pedal will keep getting firmer as you go through the system...start at the RR, then the LR, then the LF, and finally the RF....unless you don't have ABS like me. My pedal is stiff as can be with the car not running. I am running DOT4 brake fluid in mine, I almost went Motul, but decided against it since I don't race very often.

Razerx 09-05-2003 11:05 AM

Lane change,



i basically have done as you have outlined. However i didn't pump the pedal before opening the bleeder.



Here is the weird thing, as i said i thought i had air, but when I bled them a second time, i saw ZERO air bubbles. Which was why started asking on the forum if air can get trapped somewhere like the brake booster.



Reason i thought that is i own an old triumph, and there are a couple of places that are very hard to get the air out of, like the emergency splitter.



do you think i really need to pump the pedal before open each bleeder? Normally what i heard is open the bleader, push the pedal down almost all the way to the floor, close the bleader, or go for a second push if you have a lot of air, repeat until zero air bubbles.



other subject any one use potterfields?

mazdadrifter 09-05-2003 12:14 PM

if you don't have pressure in your brake lines before you open the bleeder, air could enter immediatley when you open the bleeder, especially if there is low pressure in your lines to begine with.



you have to "build a pedal" before you crack the bleeder, or just get some speed bleeders

Razerx 09-06-2003 12:59 AM

thanks for the info, speedbleeder sound like they would be a good option. but if i just crack the bleeder, fluid comes out becuase of gravity, they resevoir is higher than the bleeder, plus i have a clear hose on them point the up which fills w/ fluid if you do get an air bubble it rises, and is immediately replace by the fluid above, kinda impossible to get air in them.

amp 09-06-2003 05:15 AM


Originally Posted by Razerx' date='Sep 6 2003, 12:59 AM
...plus i have a clear hose on them point the up which fills w/ fluid if you do get an air bubble it rises, and is immediately replace by the fluid above, kinda impossible to get air in them.

not impossible..

id suggest havin it submerged in fluid instead..

Saisoku 09-07-2003 11:14 AM


Originally Posted by Razerx' date='Sep 5 2003, 09:59 PM
thanks for the info, speedbleeder sound like they would be a good option. but if i just crack the bleeder, fluid comes out becuase of gravity, they resevoir is higher than the bleeder, plus i have a clear hose on them point the up which fills w/ fluid if you do get an air bubble it rises, and is immediately replace by the fluid above, kinda impossible to get air in them.

Problem is, if you didn't build pressure before your first bleed, you already entered air into the system (the instant you opened the bleeder, air probably entered the lines due to a low pressure situation), and if you continually just bled the brake lines without building pressure first, the air will get circulated inside without being forced out.

MazdaMike 09-07-2003 10:55 PM

my pedal goes a few inches down the first push then stiffens up after id say its normal for most cars to do that

mazdadrifter 09-08-2003 05:29 PM

https://www.nopistons.com/forums/pub...1047683561.gif that might be ok for city driving, but for florida driving (old people obstical corse) and racing, I want a stiff pedal



you might just have some water in your lines mike, it happens over some time.



I try to bleed mine every other month when I'm not racing


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