Ye Olde Master Cylinder Changeout Threade! (advice needed)

[NiceGuyEddie]

it looks like at least the old flares were bubble, and the fittings were bubble. the fittings don't have that "V" in them.

the fittings do, however, look a little different than each other.

[NiceGuyEddie]

after a fantastic holiday doing all sorts of ridiculous things, the after-work temps finally dropped to a bearable level, so i got some work done.




i used some QuickSteel and made a plug so brake fluid did not drip all over my powdercoated frame when i was doing the new brake flares. it worked perfectly!





BAZINGA!

[NiceGuyEddie]

now a question. i assume the spacer was used with the master cylinder to adjust the height of the brake pedal... being high enough that it just does "not" touch the crossbar, so that's as high as it gets. and i assume my pedal was too low, and i should have not used the spacer.

now that i have the adjustable pushrod, should i still use the one spacer?

i suppose i could do a dry mockup, but it's real fiddly doing these bolts that go into the footbox, and i'd appreciate a heads-up if someone has done it before.

.

[NiceGuyEddie]

U P D A T E

• i bench-primed the master cylinder as described in the instructions.
• i got the master installed
• i adjusted the pushrod with about 1/16" between the top of the pedal arm (edge close to us) and the rubber bump-stop i fastened to the front side of the crossbar
• the good news is that there are no leaks at any of my fittings

it took a long, long time to get pressure to build up, maybe 200 pumps to get the bottom 25% to stiffen up. after that, bleeding was as usual. sometimes the fluid was a little frothy, but that turned to bubbles, and then clear fluid. i bled the brakes all around four times.

(YES i did right rear first, outer Wilwood fitting, inner fitting. then onto the driver's rear, just like Gordon told me.)

it got better and better each time (less free play in the brake pedal.) it was also nice because after going around four times, totally clean, clear brake fluid came out. the first few squirts were a little brown. but i could not get the pedal any better than the 1" of free play.

i bled the brakes all around four more times and it's still the same. there is nothing but fluid coming out.... if you look VERY carefully, sometimes you can see a few micro-bubbles coming out, but i mean the smallest micro-bubble you could possibly see with the naked eye. smaller than the period (.) on the screen you are looking at now. and that could possibly be air leaking into the fish tank tube from outside the fitting.

now when i say 1" of free play, i mean it's about the same as my clutch, 1" of play with slight springy resistance. after that, it's rock solid, i can't move it, not one bit.

i can't recall the way my old brakes were, but i don't want to judge by that. on my Tacoma, with the engine off, the brake pedal on my Tacoma also has about 1" of free play. pump it three times and then it's rock-solid. but that's a modern car with power brakes, so i probably don't want to judge by that either.

is my brake pedal supposed to be rock-hard in the all the way up position? if so, what can i do different?

almost there.....

EDIT: i just did some reading, and although i could not find an answer, i would like to add that during the 1" free-play part of the travel, i feel springy resistance in the master immediately, and the pedal always comes all the way back up.

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[CraigS]

W/o being able to feel the pedal myself, I "think" you may be done w/ bleeding. have you driven it yet? One thing I have found over the years on normal cars is that we tend to use more than normal pressure to test the pedal while sitting in the garage. It might feel a little spongey in the garage but then be just fine while driving. I am crossing my fingers for you!

[Big Blocker]

Eddie,

Are you concerned about only having 1" of free-play before it gets rock solid or the fact that it is rock solid?

Rock solid is a good thing with brakes, spongy is BAD. 4 wheel disks are going to feel completely different then a disk / drum system.

If you need more free-play, adjust your pushrod for a little more then 1/16".

Doc

[NiceGuyEddie]

Hi Guys:

i am concerned that i HAVE 1" of free play. after that, it's rock hard, it's not spongy. is the pedal supposed to be rock-hard from all the way up top?

no, I haven't driven it yet. i am positive the rotors are locked hard when depressing the brake, so I'm sure it's safe for a test drive around the block, then I can work up from there. maybe if the fluid gets hot, things will change - micro bubbles working their way up to the master, if they exist in the system?

[Silverstreak02]

I think the 1 inch is OK. What you are feeling is the pucks coming out of the calipers to press on the pads. If you had no travel at all your brakes would be locked up. Take it out for a spin and get us some 60 to 0 numbers.

Jeff

[NiceGuyEddie]

you could be right, I only tested spinning the rotors and then seeing if they were locked up when he pushed down on the pedal. we didn't check "slight resistance" with a light press on the pedal.

okay thanks guys, i think this is as far as we can go until i actually drive it. considering i had a crappy master, a crappy push-rod, and the master cylinder piped backwards, i am hoping for a huge improvement.

I have a few more mods-n-stuff to finish up before I can take the car out. check back in 1-2 weeks.



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[canuck1]

Originally Posted by NiceGuyEddie

...I have a few more mods-n-stuff to finish up before I can take the car out. check back in 1-2 weeks.



.

2 weeks? What the heck are you doing to your car? Installing a capuccino maker or maybe re-stabilizing the dilithium matrix??

Sean

[NiceGuyEddie]

haha

i have a huge summer mods list, the car is off the insurance now. i've done about ten of them, but to get the car drivable, i have to:

• put the driver's seat back in (removed it for access to pedal box) CHORE
• thoroughly clean the rims (insides) - now's the time
• thoroughly clean the front brakes and re-paint front calipers - now's the time
• put the door back on
• put the trunk lid back on.... i'll drive around the block without my hood, but no trunk - no license plate - that's asking for it!
• etc.
• wait for it to cool down to below 107°

[Silverstreak02]

Summertime is drive time for most of the forum members, but not for us. My car is sitting in the garage waiting for better weather just like yours. I imagine next year I'll start my summer mod cycle.

Jeff

[NiceGuyEddie]

the craziest irony about the Chino area is that if I lived as little as 25 miles away, I'd be driving 12 months a year, and 25 miles in the other direction, it would shorten to 8 months a year.

I finished some work today, and I am eager to get the car out in a few DAYS.

the car is uninsured, so I'll quietly creep around the block, but I don't want to take it even 1/2 mile away where there is a road big enough to do some 60-0 hard braking.

will advise,

[NiceGuyEddie]

20120828_205102.mp4 - YouTube

just to prove it happened, SUPER CHEEZY ONE-ARMED NIGHT-TIME 60-0 BRAKING VIDEO (HD!) - yes, i did it behind my house




well i feel like puttin' on a light blue suit and a pair of white shoes and lettin' out a good 'ol fashioned, southern holy-roller "HAAAAAA-LE-LUIAH!!! WE GOT US SOME POWER! STOPPIN' POWER, THAT IS!"

i can hardly believe this is my car!
remember, this is Wilwood rear, stock Mustang up front, standard pads...
i can hardly picture what it will be like when i upgrade my front brakes!

i still have the 1" travel at the top of the swing, but i hardly notice it when driving. we'll see if anything changes in the future. maybe i'll do another bleed-around after driving it for a reasonable amount of time.

thank you, everyone!

[Silverstreak02]

Did you measure the stopping distance?

Jeff

[NiceGuyEddie]

i have a few weeks to go before i do the stopping distance test. it will be the first thing i do when i get the insurance back.

[cobracruz]

Great job Eddie! Hope you get everything done on your list and I see you on the tracks. Cooler weather is just around the corner and I've got my eyes on some autocross/ willow springs dates.

[Silverstreak02]

I forgot to mention the new engine looks and sounds great.


Jeff

[NiceGuyEddie]

thanks guys, i am still in mild shock in that none of the brake fittings leaked.