Need info on brake Master Cylincer replacement
08-05-2008, 12:07 PM
#31
Drifting
HMMMM, if you examine the photo you will notice the white COUPE (me) WAAAAY ahead of numerious cabs (I count 3) WAAAY in the background...I'm just say'n...
08-06-2008, 12:20 AM
#33
Burning Brakes
Thread Starter
08-06-2008, 12:23 AM
#34
Burning Brakes
Thread Starter
Just caught up with this thread, and yes, the bleed order is very important. I'm afraid that I can't offer much help with the bleeder that can be used wet or dry; my shop used a bleeder that held about three gallons, maybe more, of fluid (it was used almost every day!), and that thing was older than dirt. I think that it was made by a company called Branick or something similar. We just plugged the reservoir overflow, replaced the reservoir cap with the machine's cap, put a few psi into the machine and went to work. I can see how the "dry" method, even with a machine, could be satisfactory. After all, that's the same as using the "pump it up," and "hold it" method that is very effective when doing a single caliper repair on a car with known history. Shannon, keep an eye on the reservoir after re-bleeding, if the "crud" returns the m/cyl might be coming apart internally.
08-06-2008, 12:40 AM
#35
Drifting
Matt, you beat me too it! I was thinking the same thing. He really needs to signal for the Cabs to pass. Dude, lead.. follow... or get out of the way!
-matt
08-06-2008, 12:48 AM
#36
Burning Brakes
Thread Starter
To test the MC, do I apply pressure with the car running?
08-06-2008, 02:06 AM
#37
Drifting
08-06-2008, 10:32 AM
#39
https://rennlist.com/forums/showthre...ghlight=master
08-06-2008, 12:12 PM
#40
Burning Brakes
Thread Starter
This is correct. I had to change mine out a few months back. You are also correct in how to test the booster.
https://rennlist.com/forums/showthre...ghlight=master
https://rennlist.com/forums/showthre...ghlight=master
And the pedal does NOT move when constant pressure is applied. That suggests the MC is "OK."
I'll do the re-bleed (in the correct order this time!) as soon as some more ATE arrives from my good buddy, amr89c4 aka Lynn.
deep_uv - you need to get Lynn to the track down there in Austin. I'm taking mine to Mid Ohio for the first time next week assuming the brakes end up ok.
08-06-2008, 02:20 PM
#41
OK, I did the tests. The pedal does move slightly when I start the car - indicates the booster is working.
And the pedal does NOT move when constant pressure is applied. That suggests the MC is "OK."
I'll do the re-bleed (in the correct order this time!) as soon as some more ATE arrives from my good buddy, amr89c4 aka Lynn.
deep_uv - you need to get Lynn to the track down there in Austin. I'm taking mine to Mid Ohio for the first time next week assuming the brakes end up ok.
And the pedal does NOT move when constant pressure is applied. That suggests the MC is "OK."
I'll do the re-bleed (in the correct order this time!) as soon as some more ATE arrives from my good buddy, amr89c4 aka Lynn.
deep_uv - you need to get Lynn to the track down there in Austin. I'm taking mine to Mid Ohio for the first time next week assuming the brakes end up ok.
Mid Ohio, I'm jealous! Have fun, you're gonna love it.
08-06-2008, 08:52 PM
#42
Burning Brakes
Thread Starter
I did the bleed today. It's better but I'm not totally satisfied. I guess I want that pedal to feel like I'm pushing on a rock wall when I hit it.
Apparently the order of the bleed is indeed VERY IMPORTANT! I did it correctly this time and when I got to the fronts, old fluid came out. That was shocking to see. When I flushed the system a few weeks ago, I used over 2L of new ATE Blue. I watched the old stuff come out and new blue flow and flow and flow before I closed the valve. I would have sworn there was no old fluid in the lines.
I guess doing it in the wrong order allowed some to remain trapped and it got pushed to the fronts when I did the rears. Or when I did the clutch.
Apparently the order of the bleed is indeed VERY IMPORTANT! I did it correctly this time and when I got to the fronts, old fluid came out. That was shocking to see. When I flushed the system a few weeks ago, I used over 2L of new ATE Blue. I watched the old stuff come out and new blue flow and flow and flow before I closed the valve. I would have sworn there was no old fluid in the lines.
I guess doing it in the wrong order allowed some to remain trapped and it got pushed to the fronts when I did the rears. Or when I did the clutch.
08-06-2008, 09:57 PM
#43
Rennlist Member
Shannon, I'm not sure if you've resealed your calipers, but if you haven't that can help with pedal "feel," but don't forget, the machine that you drive has a little bit of racer built in, and if the pedal is rock hard and "on" when you touch the pedal, you can't modulate your braking while preparing for a corner. If this will be your first time at the track, and the weather is hot, be prepared to do a quickie brake bleed during the event. Let me know about your calipers!
08-06-2008, 11:49 PM
#44
Burning Brakes
Thread Starter
Shannon, I'm not sure if you've resealed your calipers, but if you haven't that can help with pedal "feel," but don't forget, the machine that you drive has a little bit of racer built in, and if the pedal is rock hard and "on" when you touch the pedal, you can't modulate your braking while preparing for a corner. If this will be your first time at the track, and the weather is hot, be prepared to do a quickie brake bleed during the event. Let me know about your calipers!
Good point about the pedal feel and being able to modulate braking. Perhaps I'm better off with it the way it is. I can't say they feel squishy after the rebleed... they just don't seem to have the braking power I want. I'm using OE style pads (Jurid, I think). Might need something else. I'll probably burn them up at the track anyways... so what should I get to replace them? I don't plan to do many track events, but I drive some seriously twisty hilly roads and brakes are important here.
08-07-2008, 05:35 AM
#45
Burning Brakes
If your brakes can lock your wheels up...ya can't get more braking power imo. Everything else is just "feel" and "heat management" (i.e. preventing brake fade). That said, although my Carrera brakes were excellent, I "upgraded" to 930 calipers (w/ a 23 mm m/c), and it totally changed the way my brakes "feel", along with the added insurance of no brake fade when driving twisty mountain roads, etc. Now my car "feels" like I have an eleventh commandment: Thou shall stop NOW 
!
Keith
'88 CE coupe
!Keith
'88 CE coupe