Replace your master cylinder.
Gravity Bleeding....as we speak.
- Thread starter MetalSpikeRacing
- Start date
Replace your master cylinder.
- Joined
- 7 February 2010
- Messages
- 618
Billy, I thought these were X pattern? RR, LF, LR, RF
Well never mind, I guess it doesn't matter since it is still furthest to closest.
I still highly suggest building that pressure bleeder for $20( or buying one). Cheaper than a full set of speed bleeders for brakes and clutch AND can be used on both clutch, brakes and pretty much do as many different vehicles as you want.
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I'm not 100% sure if it matters but the: RR, LR, RF, LF is the pattern for furthest to closest (in a LHD US-spec car with the master cylinder and ABS on the LF of the car).
- Joined
- 7 February 2010
- Messages
- 618
What I meant was how the RR shares the same line as LF. Then LR shares the same line with RF. Instead of the traditional RR/LR line and then RF/LF line.
The X pattern being a way of still maintaining 50% braking power in the event one caliper line fails, there will still be atleast 50% power.
Thats what I read here on prime recently anyhow.
FYI, the manual specifies the "X" pattern (RR-LF, LR-RF).
I did this a month ago. Bought the stainless steel ones (ebay). Ridiculously easy.
Well, just got back from the dealer and the pedal is now worst.
Seems like I do need a new master.
What can I do to upgrade my master? is there a bigger master cylinder from another car that fit ours?
-MSR
Seems like I do need a new master.
What can I do to upgrade my master? is there a bigger master cylinder from another car that fit ours?
-MSR
Anyone has any input on this?
I am about to order a master, but if there is an upgrade then I would like to pick up one.
I just rebleed the brakes with speed bleeders on the stotechs and the rear calipers and no luck, they feel a little better but still smuch like hell.
Thank you guys,
-MSR
I am about to order a master, but if there is an upgrade then I would like to pick up one.
I just rebleed the brakes with speed bleeders on the stotechs and the rear calipers and no luck, they feel a little better but still smuch like hell.
Thank you guys,
-MSR
?
Was your braking system working fine before the install? If so, it's quite a coincidence that all of a sudden you need a new master cylinder after the install.
mmm.... You need to look at the timeline here. The initial post states that after the bleed, the pedal went to the floor(may have been the second or third bleed). If the brake pedal goes down to the floor, then or any previous time during a bleed, unless the master is brand new, there is a high probability the master will get damaged.
We have talked about this many times here on prime. The brake pedal should NEVER go past the point it normally does when the system is bled and operational. Over time there is a ridge of dirt that builds up inside the bore of the master. If you bleed using the conventional method and push the pedal past this point you push the internal seal through the dirt ridge. When this happens there is a good possibility you damage the internal seal, and the result is what is being discussed here.
I use a vacuum bleeder and NEVER use the pedal to bleed. But even if I replace brake pads, and I need to get the pistons back out after the installation, I only push the brake pedal down about 10-20% of its travel multiple times until the pedal is firm, I never push all the way to get the pedal back.
I think BrianK got it right away
.Sorry to say, but you will need the new master. Look at the bright side, it is not like you had a timing belt job go bad, and it is a $5000 problem
.HTH,
LarryB
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mmm.... You need to look at the timeline here. The initial post states that after the bleed, the pedal went to the floor(may have been the second or third bleed). If the brake pedal goes down to the floor, then or any previous time during a bleed, unless the master is brand new, there is a high probability the master will get damaged.
We have talked about this many times here on prime. The brake pedal should NEVER go past the point it normally does when the system is bled and operational. Over time there is a ridge of dirt that builds up inside the bore of the master. If you bleed using the conventional method and push the pedal past this point you push the internal seal through the dirt ridge. When this happens there is a good possibility you damage the internal seal, and the result is what is being discussed here.
I use a vacuum bleeder and NEVER use the pedal to bleed. But even if I replace brake pads, and I need to get the pistons back out after the installation, I only push the brake pedal down about 10-20% of its travel multiple times until the pedal is firm, I never push all the way to get the pedal back.
I think BrianK got it right away
Sorry to say, but you will need the new master. Look at the bright side, it is not like you had a timing belt job go bad, and it is a $5000 problem
HTH,
LarryB
I didn't know this. Thanks for the insight!
Ya, I will order today .
So just buy a oem one? Is there any upgrades?
Is the oem one ok with the larger pistons from the bigger brakes?
-MSR
So just buy a oem one? Is there any upgrades?
Is the oem one ok with the larger pistons from the bigger brakes?
-MSR
I replaced my master cylinder this summer. 20min max.
I never had any issues until I changed the brake fluid. I suspect that the new fluid was not compatable with the old. Anyway, $250.00 for the part. 20 min to change it out and 1 hour to bleed the system. Very easy to do.
I had the same issue you did. The system seemed ok until the car got hot. Then the pedal would go to the floor with slight presure.
I pre-bled the Master before installing it. Just to rid the majority of air in the cylinder. Not necessary but easy to do.
My brake pedal is rock hard ever since.
I never had any issues until I changed the brake fluid. I suspect that the new fluid was not compatable with the old. Anyway, $250.00 for the part. 20 min to change it out and 1 hour to bleed the system. Very easy to do.
I had the same issue you did. The system seemed ok until the car got hot. Then the pedal would go to the floor with slight presure.
I pre-bled the Master before installing it. Just to rid the majority of air in the cylinder. Not necessary but easy to do.
My brake pedal is rock hard ever since.
Interesting, never thought about that. Having built 3 spec miata race cars and 2 more miata track cars (all with 140-230K+ miles), some of which did 3-25 hour races, I have never had a problem bleeding the brakes the 'traditional' way by pushing the pedal to the floor numerous times in the bleeding process.mmm.... You need to look at the timeline here. The initial post states that after the bleed, the pedal went to the floor(may have been the second or third bleed). If the brake pedal goes down to the floor, then or any previous time during a bleed, unless the master is brand new, there is a high probability the master will get damaged.
We have talked about this many times here on prime. The brake pedal should NEVER go past the point it normally does when the system is bled and operational. Over time there is a ridge of dirt that builds up inside the bore of the master. If you bleed using the conventional method and push the pedal past this point you push the internal seal through the dirt ridge. When this happens there is a good possibility you damage the internal seal, and the result is what is being discussed here.
I use a vacuum bleeder and NEVER use the pedal to bleed. But even if I replace brake pads, and I need to get the pistons back out after the installation, I only push the brake pedal down about 10-20% of its travel multiple times until the pedal is firm, I never push all the way to get the pedal back.
I think BrianK got it right away
Sorry to say, but you will need the new master. Look at the bright side, it is not like you had a timing belt job go bad, and it is a $5000 problem
HTH,
LarryB
My NSX has 130K miles on it and I just replaced the rotors and pads on my M3 last weekend (which just turned 150K miles) -amongst many other cars I've worked on, and never had problems with the master cylinder extending beyond the 'normal distance' and causing dirt to ruin the seal when pressing the brake pedal to the floor.
I'm not saying it's not possible to ruin the master cylinder by pressing the brake pedal to the floor when bleeding the brakes the 'traditional' way, but from my experience I don't think it's very likely.
0.02
I think if the MC is newer and/or the fluid was changed frequently (as in a racecar) it may endure less build-up (not sure about that, but it would make sense).
I've definitely finished-off a MC by pedal bleeding and using too long of a stroke. It was already very high-miled, but I bled the fluid in my MR2 before one of the first track events I did ~4 years ago, and I lost front brakes on the short test drive I did. Sure enough, dead MC seal. Since then I've either used basically half a pedal stroke or more recently a vacuum bleeder.
I've definitely finished-off a MC by pedal bleeding and using too long of a stroke. It was already very high-miled, but I bled the fluid in my MR2 before one of the first track events I did ~4 years ago, and I lost front brakes on the short test drive I did. Sure enough, dead MC seal. Since then I've either used basically half a pedal stroke or more recently a vacuum bleeder.
Yup, pretty simple. I changed the one on my NSX when it was working fine. I was changing literally everything else (lines, calipers, ABS unit) so I just did that as well to eliminate a potential headache.
Also, I agree with Larry that bench bleeding is probably the way to go. I didn't and you go through a of fluid to get all the air out when it's installed dry.
Also, I agree with Larry that bench bleeding is probably the way to go. I didn't and you go through a of fluid to get all the air out when it's installed dry.
In regard to the Miata's I suspect the fluid is always clean, bleed frequently, and little dirt or none ever built up. Again this is not a 100% failure, but it is not 1/1000 either
. I have heard this 20+ times over the last 10 years or so, mostly street cars, higher mileage, infrequent brake bleeds. With so many cars that I do not really know the detailed history, I just always play it safe. When I install a new master, I do not even give it a thought, and even bench bleed at full stroke.Regards,
LarryB
20+ times a year, 10 years = 2-3x a year. How many people do you interact with a year at the track or who track their cars? I'm not doubting it happens atall, I just don't think its more likely to happen than not. Since its easy to replace and bleeding the traditional way is easy, quick, and efficient, that's what I tend to do -even on those miatas that were purchased with said mileage; some of which probably had the original brake fluid in it before they became track/race cars.In regard to the Miata's I suspect the fluid is always clean, bleed frequently, and little dirt or none ever built up. Again this is not a 100% failure, but it is not 1/1000 either
Regards,
LarryB
In regard to the Miata's I suspect the fluid is always clean, bleed frequently, and little dirt or none ever built up. Again this is not a 100% failure, but it is not 1/1000 either
Regards,
LarryB
Larry is right on , you have to compare apples with apples, in tech school (many years ago) we were taught to place a wooden block under the brake pedal to limit the master cyl. piston travel, 30 yrs later iam doing an adult ed class, one of my students tells us if his shop has a caliper or wheel cyl. leak they also replace the master cyl, for some reason they seem to fail a short period later :wink:
To my knowledge Larry is the sole provider of mechanical assistance to 4 true track driven nsx,and probably another 5 or so occasional hpde cars...plus the countless street nsx...and soon to be pos Ford:tongue:
Actually I am refering to street driven cars mostly. The track folks, just like you, are always diligent and keep there fluid changed quite often. This are from modtly the folks that when you say: "When did you last change you brake fluid?", they say: "not sure"
In your case, if the fluid was old originally, luck is on your side
.Regards,
LarryB
Ok, well I just ordered the master cylinder.
Larry, could you please explain how the bench bleeding is done?
I will aprecciate that.
Larry, could you please explain how the bench bleeding is done?
I will aprecciate that.
