My current setup is as follows:

-Complete GSR disc brake swap
-Stainless lines
-Stock pads
-40/40 prop valve
-Stock cx master cylinder and booster

I have been too lazy to switch out the master cylinder and I've had no problems until today. I had my car parked in a hot parking lot for about 4 hours and when I got back out on the street I had really bad problems with the brakes fading. It would stop fine, but then the pedal would keep sinking. If I was stopped I would have to keep pusing in to avoid rolling.

I am taking a trip out of town tonight and Im starting to think it might not be a smart idea. I'm thinking the master cylinder is dying. Any advice?

 

Check the valve (I forgot how to but I'm pretty sure you can find it if search). You can also determine what is going on too by checking it that way, I think.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ABK &raquo;</TD></TR><TR><TD CLASS="quote">Check the valve (I forgot how to but I'm pretty sure you can find it if search). You can also determine what is going on too by checking it that way, I think.</TD></TR></TABLE>

Say what?

Well it cooled off now and seems to be ok. I think I will finally throw in the new cylinder with some decent brake fluid next weekend.

 

there is the valve that hold the vacume that goes from the motor to the booster, if it's messed up you will experience fade but you will never know when it's coming.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by White Lightnin &raquo;</TD></TR><TR><TD CLASS="quote">

Say what?

Well it cooled off now and seems to be ok. I think I will finally throw in the new cylinder with some decent brake fluid next weekend.</TD></TR></TABLE>

If it's when it's heated, it sounds like your fluid is 'boiling' which means you have water in it. You should flush the whole system before there is a full failure instead of just fade.

 

I'll be replacing the master cylinder this weekend and bleeding the whole system. Hopefully that will take care of things. Need to get some better pads, but money is tight.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ABK &raquo;</TD></TR><TR><TD CLASS="quote">there is the valve that hold the vacume that goes from the motor to the booster, if it's messed up you will experience fade but you will never know when it's coming.</TD></TR></TABLE>

not necessarily true. when your booster dies from lack of vacume it will be harder for you to stop your car since the booster is not helping you put pressure in the lines. low line pressure does not equal fade. it also doesnt explain why the pedal sank to the floor. i would suspect a leaking mc or crappy fluid.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Mr. Choi &raquo;</TD></TR><TR><TD CLASS="quote">

not necessarily true. when your booster dies from lack of vacume it will be harder for you to stop your car since the booster is not helping you put pressure in the lines. low line pressure does not equal fade. it also doesnt explain why the pedal sank to the floor. i would suspect a leaking mc or crappy fluid.</TD></TR></TABLE>

I'm thinking all of the above. The M/C is dying and the fluid went from looking fresh to looking like crap. I'm gonna throw in some speed bleaders, the GSR master cylinder, and maybe new pads this weekend?

Any pad suggestions for simple daily driving? I don't feel like searching

 

Just for comfort...i had the same problem last summer. It was my master cylinder. Havent had problems since.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by White Lightnin &raquo;</TD></TR><TR><TD CLASS="quote">

The M/C is dying and the fluid went from looking fresh to looking like crap. </TD></TR></TABLE>

Then the fluid is definitely overheating. Fluid begins to look 'old' or dirty from heat cycling and water retention.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by White Lightnin &raquo;</TD></TR><TR><TD CLASS="quote">

Any pad suggestions for simple daily driving? I don't feel like searching </TD></TR></TABLE>

When I'm working on other's cars, I usually use ricer zone specials, or whatever I can get from the parts store for a daily driver. Cheap, and they work okay. You could always try OEM, but I'm not sure how much they are. If you want something with a little more bite, I'd go with Hawk, lots of bang for the buck.

 

Rebleed your brakes...

As for pads:
Carbotech Panthers or Axxis Ultimates

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by White Lightnin &raquo;</TD></TR><TR><TD CLASS="quote">I'm thinking all of the above. The M/C is dying and the fluid went from looking fresh to looking like crap. I'm gonna throw in some speed bleaders, the GSR master cylinder, and maybe new pads this weekend?

Any pad suggestions for simple daily driving? I don't feel like searching </TD></TR></TABLE>

Don't use speed bleeders. I've got a set. Less than a year later, the one way valves failed, so when you try to bleed the brakes with them, you can actually watch it suck fluid back up into the caliper. Next time I bleed the brakes, I'm switching back to the oem bleeders.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by MichaelJComputer &raquo;</TD></TR><TR><TD CLASS="quote">Rebleed your brakes...</TD></TR></TABLE>

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by kommon_sense &raquo;</TD></TR><TR><TD CLASS="quote">

Don't use speed bleeders. I've got a set. Less than a year later, the one way valves failed, so when you try to bleed the brakes with them, you can actually watch it suck fluid back up into the caliper. Next time I bleed the brakes, I'm switching back to the oem bleeders.</TD></TR></TABLE>

Too late just ordered them. I think they will work out based on the threads I read.

 

It's not brake fade it's the MC. You're brakes couldn't possibly fade after just getting hot by sitting in a parking lot. I had the same problem on my old DA. When it was hot under the hood (hot day or driving for a long time) the pedal would sink to the floor. It wasn't as bad when it was cool. I replace the MC and it was fixed.

As for pads, I like Axxis Ultimates, I run them on the street and I've tracked them once and I like them a lot. I used higher temp brake fluid for the track and there was no brake fade (even in a heavy 99 coupe)! I'll have a set for sale right now, I'll be putting them on ebay in the next couple days. PM if interested.

-Steve

OH BTW..... I've had speed bleeders on 2 different cars and I love them

 

Same here brake fading so it could be the vacuum lines cause i bleeded the brake lines and nothing. will a compete flush help.

 

So u say its the mc thats what i was thinking too. can i upgrade my mc even though i have rear drums. the reason i want to upgrade so it brake faster.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by civic_type_r &raquo;</TD></TR><TR><TD CLASS="quote">So u say its the mc thats what i was thinking too. can i upgrade my mc even though i have rear drums. the reason i want to upgrade so it brake faster.</TD></TR></TABLE>

I personally wouldn't upgrade the MC if you still have rear drums. That could throw off the whole front-to-rear brake bias and cause some strange braking issues (i.e. rears lock up too easily). I would stick to a stock MC if you're going to keep the stock rears. IMO there's really nothing much wrong with drum brakes in the rear. They just need to be adjusted every once in a while and they work great.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by nonsense &raquo;</TD></TR><TR><TD CLASS="quote">

I personally wouldn't upgrade the MC if you still have rear drums. That could throw off the whole front-to-rear brake bias and cause some strange braking issues (i.e. rears lock up too easily). I would stick to a stock MC if you're going to keep the stock rears. IMO there's really nothing much wrong with drum brakes in the rear. They just need to be adjusted every once in a while and they work great. </TD></TR></TABLE>

Thanks mang ! the reason i want to upgrade is because I want all to brake at the same time but i guess i have to swap the rear drums.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by nonsense &raquo;</TD></TR><TR><TD CLASS="quote">

I personally wouldn't upgrade the MC if you still have rear drums. That could throw off the whole front-to-rear brake bias and cause some strange braking issues (i.e. rears lock up too easily). I would stick to a stock MC if you're going to keep the stock rears. IMO there's really nothing much wrong with drum brakes in the rear. They just need to be adjusted every once in a while and they work great. </TD></TR></TABLE>

uhh ok? the mc controls brake bias? sorry bro its the proportioning valve that does that. you can upgrade your mc with no problems. with a bigger mc the pedal will travel less and you will need to press on the pedal harder to get same braking power. its fine to upgrade the mc even with drums.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Mr. Choi &raquo;</TD></TR><TR><TD CLASS="quote">

uhh ok? the mc controls brake bias? sorry bro its the proportioning valve that does that. you can upgrade your mc with no problems. with a bigger mc the pedal will travel less and you will need to press on the pedal harder to get same braking power. its fine to upgrade the mc even with drums.</TD></TR></TABLE>

so what would be the point of upgrading the mc if i have to press the pedal harder to brake harder i thought this was the other way around.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Mr. Choi &raquo;</TD></TR><TR><TD CLASS="quote">

uhh ok? the mc controls brake bias? sorry bro its the proportioning valve that does that. you can upgrade your mc with no problems. with a bigger mc the pedal will travel less and you will need to press on the pedal harder to get same braking power. its fine to upgrade the mc even with drums.</TD></TR></TABLE>

There a lot more to brake bias than a prop valve. Even brake pad and rotor choices can effect bias. For more info in this there are a few good articles writen by Grassroots Motorsports Magazine on brake bias. Changing a MC without properly matching it with the other components is not recommeded, but since you did it with rear drums and didn't see any issues on the streets under hard braking in the rain it should be ok. If you haven't already done this exact swap then you should probably not comment that it'll be ok.

Steve

 

seals in your master may be going. It's probably not that you need to bleed them because being hot wouldn't affect any air in the system. The peddle would sink no matter what. Bench bleed the master before you put it on, bleed the system and I bet you'll be good to go good luck

 

Ok well I lost the fitting to my 1" master cylinder so I can't do the swap out. No place has the damn fitting even the Acura dealership. Anyone know where I can get one.

I was just going to get the 91 ex 15/16 master cylinder but my card was maxed out.

So I flushed the system and cleaned out the old one. It felt ok for a bit til I had to use my e brake to stop. Looks like I am **** out of luck for a bit.

 

BUMP!

What size is that fitting? Anyone know?